Racism, by its perhaps simplest definition, is prejudice and discrimination based on race. One with racist beliefs might hate certain groups of people according to their race (i.e., bigotry), or in the case of institutional racism, certain racial groups may be denied rights or benefits. Racism inherently starts with the assumption that there are taxonomic differences between different groups of people. Without this assumption, prejudices against different peoples would be categorized as being prejudices related to national or regional origin, religion, occupation, social status or some other distinction.
According to the United Nations conventions, there is no distinction between the term racial discrimination and ethnic discrimination, see below.
While the term racism usually denotes race-based prejudice, violence, discrimination, or oppression, the term can also have varying and hotly contested definitions. Racialism is a related term, sometimes intended to avoid these negative meanings. According to the Oxford English Dictionary, racism is a belief or ideology that all members of each racial group possess characteristics or abilities specific to that race, especially to distinguish it as being either superior or inferior to another racial group or racial groups. The Merriam-Webster's Dictionary defines racism as a belief that race is the primary determinant of human traits and capacities and that racial differences produce an inherent superiority of a particular racial group, and that it is also the prejudice based on such a belief. The Macquarie Dictionary defines racism as: "the belief that human races have distinctive characteristics which determine their respective cultures, usually involving the idea that one's own race is superior and has the right to rule or dominate others."
According to the United Nations Convention on the Elimination of All Forms of Racial Discrimination,
the term "racial discrimination" shall mean any distinction, exclusion, restriction or preference based on race, colour, descent, or national or ethnic origin which has the purpose or effect of nullifying or impairing the recognition, enjoyment or exercise, on an equal footing, of human rights and fundamental freedoms in the political, economic, social, cultural or any other field of public life. '
This definition does not make any difference between prosecutions based on ethnicity and race, in part because the distinction between the ethnicity and race remains debatable among anthropologists. According to British law, racial group means "any group of people who are defined by reference to their race, colour, nationality (including citizenship) or ethnic or national origin".
Some sociologists have defined racism as a system of group privilege. In Portraits of White Racism David Wellman (1993) has defined racism as "culturally sanctioned beliefs, which, regardless of intentions involved, defend the advantages whites have because of the subordinated position of racial minorities,” (Wellman 1993: x). Sociologists Noel Cazenave and Darlene Alvarez Maddern define racism as “...a highly organized system of 'race'-based group privilege that operates at every level of society and is held together by a sophisticated ideology of color/'race' supremacy. Racist systems include, but cannot be reduced to, racial bigotry,” (Cazenave and Maddern 1999: 42). Sociologist and former American Sociological Association president Joe Feagin argues that the United States can be characterized as a "total racist society" because racism is used to organize every social institution (Feagin 2000, p. 16).
More recently, Feagin has articulated a comprehensive theory of racial oppression in the U.S. in his book Systemic Racism: A Theory of Oppression (Routledge, 2006). Feagin examines how major institutions have been built upon racial oppression which was not an accident of history, but was created intentionally by white Americans. In Feagin's view, white Americans labored hard to create a system of racial oppression in the 17th century and have worked diligently to maintain the system ever since. While Feagin acknowledges that changes have occurred in this racist system over the centuries, he contends that key and fundamental elements have been reproduced over nearly four centuries, and that U.S. institutions today reflect the racialized hierarchy created in the 17th century. Today, as in the past, racial oppression is not just a surface-level feature of this society, but rather pervades, permeates, and interconnects all major social groups, networks, and institutions across the society. Feagin's definition stands in sharp contrast to psychological definitions that assume racism is an "attitude" or an irrational form of bigotry that exists apart from the organization of social structure.
Racial discrimination is treating people differently through a process of social division into categories not necessarily related to race. Racial segregation policies may officialize it, but it is also often exerted without being legalized. Researchers, including Dean Karlan and Marianne Bertrand, at the MIT and the University of Chicago found in a 2003 study that there was widespread discrimination in the workplace against job applicants whose names were merely perceived as "sounding black". These applicants were 50% less likely than candidates perceived as having "white-sounding names" to receive callbacks for interviews. The researchers view these results as strong evidence of unconscious biases rooted in the United States' long history of discrimination (i.e. Jim Crow laws, etc.) 
Institutional racism (also known as structural racism, state racism or systemic racism) is racial discrimination by governments, corporations, educational institutions or other large organizations with the power to influence the lives of many individuals. Stokely Carmichael is credited for coining the phrase institutional racism in the late 1960s. He defined the term as "the collective failure of an organization to provide an appropriate and professional service to people because of their colour, culture or ethnic origin". 
Maulana Karenga argued that racism constituted the destruction of culture, language, religion and human possibility, and that the effects of racism were "the morally monstrous destruction of human possibility involved redefining African humanity to the world, poisoning past, present and future relations with others who only know us through this stereotyping and thus damaging the truly human relations among peoples." 
Economics and racism
Historical economic or social disparity is alleged to be a form of discrimination which is caused by past racism and historical reasons, affecting the present generation through deficits in the formal education and kinds of preparation in the parents' generation, and, through primarily unconscious racist attitudes and actions on members of the general population. (e.g. A member of race Y, Mary, has her opportunities adversely affected (directly and/or indirectly) by the mistreatment of her ancestors of race Y.) The common hypothesis embraced by classical economists is that competition in a capitalist economy decreases the impact of discrimination. The thinking behind the hypothesis is that discrimination imposes a cost on the employer, and thus a profit-driven employer will avoid racist hiring policies.
Declarations against racial discrimination
Racial discrimination contradicts the 1776 United States Declaration of Independence, the 1789 Declaration of the Rights of Man and of the Citizen issued during the French Revolution and the 1948 Universal Declaration of Human Rights, signed after World War II, which all postulate equality between all human beings.
In 1950, UNESCO suggested in The Race Question —a statement signed by 21 scholars such as Ashley Montagu, Claude Lévi-Strauss, Gunnar Myrdal, Julian Huxley, etc. — to "drop the term race altogether and instead speak of ethnic groups". The statement condemned scientific racism theories which had played a role in the Holocaust. It aimed both at debunking scientific racist theories, by popularizing modern knowledge concerning "the race question," and morally condemned racism as contrary to the philosophy of the Enlightenment and its assumption of equal rights for all. Along with Myrdal's An American Dilemma: The Negro Problem and Modern Democracy (1944), The Race Question influenced the 1954 U.S. Supreme Court desegregation decision in "Brown v. Board of Education of Topeka". 
The United Nations uses the definition of racial discrimination laid out in the International Convention on the Elimination of All Forms of Racial Discrimination, adopted in 1966:
... any distinction, exclusion, restriction or preference based on race, color, descent, or national or ethnic origin which has the purpose or effect of nullifying or impairing the recognition, enjoyment or exercise, on an equal footing, of human rights and fundamental freedoms in the political, economic, social, cultural or any other field of public life. (Part 1 of Article 1 of the U.N. International Convention on the Elimination of All Forms of Racial Discrimination) 
In 2001, the European Union explicitly banned racism along with many other forms of social discrimination in the Charter of Fundamental Rights of the European Union, the legal effect of which, if any, would necessarily be limited to Institutions of the European Union: "Article 21 of the charter prohibits discrimination on any ground such as race, color, ethnic or social origin, genetic features, language, religion or belief, political or any other opinion, membership of a national minority, property, disability, age or sexual orientation and also discrimination on the grounds of nationality." 
Politics and Racism
As an ideology, racism existed during the 19th century as "scientific racism", which attempted to provide a racial classification of humanity.  Although such racist ideologies have been widely discredited after World War II and the Holocaust, the phenomena of racism and of racial discrimination have remained widespread all over the world.
It was already noted by DuBois that in making the difference between races, it is not race that we think about, but culture: “… a common history, common laws and religion, similar habits of thought and a conscious striving together for certain ideals of life”  Late nineteenth century nationalists were the first to embrace contemporary discourses on "race", ethnicity and "survival of the fittest" to shape new nationalist doctrines. Ultimately, race came to represent not only the most important traits of the human body, but was also regarded as decisively shaping the character and personality of the nation.  According to this view, culture is the physical manifestation created by ethnic groupings, as such fully determined by racial characteristics. Culture and race became considered intertwined and dependent upon each other, sometimes even to the extent of including nationality or language to the set of definition. Pureness of race tended to be related to rather superficial characteristics that were easily addressed and advertised, such as blondness. Racial qualities tended to be related to nationality and language rather than the actual geographic distribution of racial characteristics. In the case of Nordicism, the denomination "Germanic" became virtually equivalent to superiority of race.
Bolstered by some nationalist and ethnocentric values and achievements of choice, this concept of racial superiority evolved to distinguish from other cultures, that were considered inferior or impure. This emphasis on culture corresponds to the modern mainstream definition of racism: "Racism does not originate from the existence of ‘races’. It creates them through a process of social division into categories: anybody can be racialised, independently of their somatic, cultural, religious differences."  This definition explicitly ignores the fiery polemic on the biological concept of race, still subject to scientific debate. In the words of David C. Rowe "A racial concept, although sometimes in the guise of another name, will remain in use in biology and in other fields because scientists, as well as lay persons, are fascinated by human diversity, some of which is captured by race." 
Until recent history this racist abuse of physical anthropology has been politically exploited. Apart from being unscientific, racial prejudice became subject to international legislation. For instance, the Declaration on the Elimination of all Forms of Racial Discrimination, adopted by the United Nations General Assembly on November 20, 1963, address racial prejudice explicitly next to discrimination for reasons of race, colour or ethnic origin (Article I). 
Racism has been a motivating factor in social discrimination, racial segregation, hate speech and violence (such as pogroms, genocides and ethnic cleansings). Despite the persistence of racial stereotypes, humor and epithets in much everyday language, racial discrimination is illegal in many countries. Some politicians have practiced race baiting in an attempt to win votes.
After the Napoleonic Wars, Europe was confronted with the new "nationalities question," leading to ceaseless reconfigurations of the European map, on which the frontiers between the states had been delimited during the 1648 Peace of Westphalia. Nationalism had made its first, striking appearance with the invention of the levée en masse by the French revolutionaries, thus inventing mass conscription in order to be able to defend the newly-founded Republic against the Ancien Régime order represented by the European monarchies. This led to the French Revolutionary Wars (1792-1802) and then to the Napoleonic conquests, and to the subsequent European-wide debates on the concepts and realities of nations, and in particular of nation-states. The Westphalia Treaty had divided Europe into various empires and kingdoms (Ottoman Empire, Holy Roman Empire, Swedish Empire, Kingdom of France, etc.), and for centuries wars were waged between princes (Kabinettskriege in German).
Modern nation-states appeared in the wake of the French Revolution, with the formation of patriotic sentiments for the first time in Spain during the Peninsula War (1808-1813 - known in Spanish as the Independence War). Despite the restoration of the previous order with the 1815 Congress of Vienna, the "nationalities question" became the main problem of Europe during the Industrial Era, leading in particular to the 1848 Revolutions, the Italian unification completed during the 1871 Franco-Prussian War, which itself culminated in the proclamation of the German Empire in the Hall of Mirrors in the Palace of Versailles, thus achieving the German unification. Meanwhile, the Ottoman Empire, the "sick man of Europe," was confronted with endless nationalist movements, which, along with the dissolving of the Austrian-Hungarian Empire, would lead to the creation after World War I of the various nation-states of the Balkans, which were always confronted, and remain so today, with the existence of "national minorities" in their borders.  Ethnic nationalism, which advocated the belief in a hereditary membership of the nation, made its appearance in the historical context surrounding the creation of the modern nation-states. One of its main influences was the Romantic nationalist movement at the turn of the 19th century, represented by figures such as Johann Herder (1744-1803), Johan Fichte (1762-1814) in the Addresses to the German Nation (1808), Friedrich Hegel (1770-1831), or also, in France, Jules Michelet (1798-1874). It was opposed to liberal nationalism, represented by authors such as Ernest Renan (1823-1892), who conceived of the nation as a community which, instead of being based on the Volk ethnic group and on a specific, common language, was founded on the subjective will to live together ("the nation is a daily plebiscite", 1882) or also John Stuart Mill (1806-1873). 
Ethnic nationalism quickly blended itself with scientific racist discourses, as well as with "continental imperialist" (Hannah Arendt, 1951) discourses, for example in the pan-Germanism discourses, which postulated the racial superiority of the German Volk. The Pan-German League (Alldeutscher Verband), created in 1891, promoted German imperialism, "racial hygiene" and was opposed to intermarriage with Jews. Another, popular current, the Völkisch movement, was also an important proponent of the German ethnic nationalist discourse, which it also combined with modern anti-semitism. Members of the Völkisch movement, in particular the Thule Society, would participate in the founding of the German Workers' Party (DAP) in Munich in 1918, the predecessor of the NSDAP Nazi party. Pan-Germanism played a decisive role in the interwar period of the 1920s-1930s. 
These currents began to associate the idea of the nation with the biological concept of a "master race" (often the "Aryan race" or "Nordic race") issued from the scientific racist discourse. They conflated nationalities with ethnic groups, called "races", in a radical distinction from previous racial discourses which posited the existence of a "race struggle" inside the nation and the state itself. Furthermore, they believed that political boundaries should mirror these alleged racial and ethnic groups, thus justifying ethnic cleansing in order to achieve "racial purity" and also to achieve ethnic homogeneity in the nation-state.
Such racist discourses, combined with nationalism, were not however limited to pan-Germanism. In France, the transition from Republican, liberal nationalism, to ethnic nationalism, which made nationalism a characteristic of far-right movements in France, took place during the Dreyfus Affair at the end of the 19th century. During several years, a nation-wide querelle affected French society, concerning the alleged treason of Alfred Dreyfus, a French Jewish military officer. The country polarized itself into two opposite camps, one represented by Emile Zola, who wrote J'accuse in defense of Alfred Dreyfus, and the other represented by the nationalist poet Maurice Barrès (1862-1923), one of the founders of the ethnic nationalist discourse in France. At the same time, Charles Maurras (1868-1952), founder of the monarchist Action française movement, theorized the "anti-France," composed of the "four confederate states of Protestants, Jews, Freemasons and foreigners" (his actual word for the latter being the pejorative métèques). Indeed, to him the first three were all "internal foreigners," who threatened the ethnic unity of the French people.
Debates over the origins of racism often suffer from a lack of clarity over the term. Many use the term "racism" to refer to more general phenomena, such as xenophobia and ethnocentrism, although scholars attempt to clearly distinguish those phenomena from racism as an ideology or from scientific racism, which has little to do with ordinary xenophobia.Others conflate recent forms of racism with earlier forms of ethnic and national conflict. In most cases, ethno-national conflict seems to owe itself to conflict over land and strategic resources. In some cases ethnicity and nationalism were harnessed to rally combatants in wars between great religious empires (for example, the Muslim Turks and the Catholic Austro-Hungarians).
Notions of race and racism often have played central roles in such ethnic conflicts. Historically, when an adversary is identified as "other" based on notions of race or ethnicity (particularly when "other" is construed to mean "inferior"), the means employed by the self-presumed "superior" party to appropriate territory, human chattel, or material wealth often have been more ruthless, more brutal, and less constrained by moral or ethical considerations. According to historian Daniel Richter, Pontiac's Rebellion saw the emergence on both sides of the conflict of "the novel idea that all Native people were 'Indians,' that all Euro-Americans were 'Whites,' and that all on one side must unite to destroy the other." (Richter, Facing East from Indian Country, p. 208) Basil Davidson insists in his documentary, Africa: Different but Equal, that racism, in fact, only just recently surfaced—as late as the 1800s, due to the need for a justification for slavery in the Americas.
The idea of slavery as an "equal-opportunity employer" was denounced with the introduction of Christian theory in the West. Maintaining that Africans were "subhuman" was the only loophole in the then accepted law that "men are created equal" that would allow for the sustenance of the Triangular Trade. New peoples in the Americas, possible slaves, were encountered, fought, and ultimately subdued, but then due to western diseases, their populations drastically decreased. Through both influences, theories about "race" developed, and these helped many to justify the differences in position and treatment of people whom they categorized as belonging to different races (see Eric Wolf's Europe and the People without History).
Juan Ginés de Sepúlveda argued that during the Valladolid controversy in the middle of the 16th century that the Native Americans were natural slaves because they had no souls. In Asia, the Chinese and Japanese Empires were both strong colonial powers, with the Chinese making colonies and vassal states of much of East Asia throughout history, and the Japanese doing the same in the 19th-20th centuries. In both cases, the Asian imperial powers believed they were ethnically and racially preferenced too.
Academic racism was pushed by white supremacists during the period when white people garnered great profits from slavery and colonialism. Academic racism had the effect of attempting to deny the culture, history and ancestry from the victims of the profitable slave and colonial systems. Owen 'Alik Shahadah comments on this racism by stating: "Historically Africans are made to sway like leaves on the wind, impervious and indifferent to any form of civilization, a people absent from scientific discovery, philosophy or the higher arts. We are left to believe that almost nothing can come out of Africa, other than raw material." Scottish philosopher and economist David Hume said, "I am apt to suspect the Negroes to be naturally inferior to the Whites. There scarcely ever was a civilised nation of that complexion, nor even any individual, eminent either in action or in speculation. No ingenious manufacture among them, no arts, no sciences." German philosopher Immanuel Kant stated: "The yellow Indians do have a meagre talent. The Negroes are far below them, and at the lowest point are a part of the American people." 
In the nineteenth century, the German philosopher Georg Wilhelm Friedrich Hegel declared that "Africa is no historical part of the world." Hegel further claimed that blacks had no "sense of personality; their spirit sleeps, remains sunk in itself, makes no advance, and thus parallels the compact, undifferentiated mass of the African continent" (On Blackness Without Blacks: Essays on the Image of the Black in Germany, Boston: C.W. Hall, 1982, p. 94). Fewer than 30 years before Nazi Germany started World War II, the German Otto Weininger, claimed: "A genius has perhaps scarcely ever appeared amongst the negroes, and the standard of their morality is almost universally so low that it is beginning to be acknowledged in America that their emancipation was an act of imprudence" (Sex and Character, New York: G.P. Putnam, 1906, p. 302).
The German conservative Oswald Spengler remarked on what he perceived as the culturally degrading influence of Africans in modern Western culture: in The Hour of Decision Spengler denounced "the 'happy ending' of an empty existence, the boredom of which has brought to jazz music and Negro dancing to perform the Death March for a great Culture" (The Hour of Decision, pp. 227-228). During the Nazi era, German scientists rearranged academia to support claims of a grand Aryan agent behind the splendors of all human civilizations, including India and Ancient Egypt. 
(Völkerschau) in Stuttgart (Germany) in 1928. People Show (Völkerschau) in Stuttgart (Germany) in 1928.
The modern biological definition of race developed in the 19th century with scientific racist theories. The term scientific racism refers to the use of faulty science to justify and support racist beliefs, which goes back to at least the early 18th century, though it gained most of its influence in the mid-19th century, during the New Imperialism period. Also known as academic racism, such theories first needed to overcome the Church's resistance to positivists accounts of history, and its support of monogenism, that is that all human beings were originated from the same ancestors, in accordance with creationist accounts of history.
These racist theories put forth on scientific hypothesis were combined with unilineal theories of social progress which postulated the superiority of the European civilization over the rest of the world. Furthermore, they frequently made use of the idea of "survival of the fittest", a term coined by Herbert Spencer in 1864, associated with ideas of competition which were named social Darwinism in the 1940s. Charles Darwin himself opposed the idea of rigid racial differences in The Descent of Man (1871) in which he argued that humans were all of one species, sharing common descent. He recognised racial differences as varieties of humanity, and emphasised the close similarities between people of all races in mental faculties, tastes, dispositions and habits, while still contrasting the culture of the "lowest savages" with European civilization.  
At the end of the 19th century, proponents of scientific racism intertwined themselves with eugenics discourses of "degeneration of the race" and "blood heredity." Henceforth, scientific racist discourses could be defined as the combination of polygenism, unilinealism, social darwinism and eugenism. They found their scientific legitimacy on physical anthropology, anthropometry, craniometry, phrenology, physiognomy and others now discredited disciplines in order to formulate racist prejudices.
Before being disqualified in the 20th century by the American school of cultural anthropology (Franz Boas, etc.), the British school of social anthropology (Bronisław Malinowski, Alfred Radcliffe-Brown, etc.), the French school of ethnology (Claude Lévi-Strauss, etc.), as well as the discovery of the neo-Darwinian synthesis, such sciences, in particular anthropometry, were used to deduce behaviours and psychological characteristics from outward, physical appearances. The neo-Darwinian synthesis, first developed in the 1930s, eventually led to a gene-centered view of evolution in the 1960s, which seemed at first to be sufficient proof of the inanity of the "scientific racist" theories of the 19th centuries, which based their conception of evolution on "races", a concept which first appeared to lose any sense at the genetic level. However, the modern resurgence of racist theories, in particular those related to the race and intelligence controversy, seems to show that genetics could also be used for ideological, racist purposes.
Heredity and eugenics
The first theory of eugenics was developed in 1869 by Francis Galton (1822-1911), who used the then popular concept of degeneration. He applied statistics to study human differences and the alleged "inheritance of intelligence," foreshadowing future uses of "intelligence testing" by the anthropometry school. Such theories were vividly described by the writer Emile Zola (1840-1902), who started publishing in 1871 a twenty-novel cycle, Les Rougon-Macquart, where he linked heredity to behavior. Thus, Zola described the high-born Rougons as those involved in politics (Son Excellence Eugène Rougon) and medicine (Le Docteur Pascal) and the low-born Macquarts as those fatally falling into alcoholism (L'Assommoir), prostitution (Nana), and homicide (La Bête humaine).
During the rise of Nazism in Germany, some scientists in Western nations worked to debunk the regime's racial theories. A few argued against racist ideologies and discrimination, even if they believed in the alleged existence of biological races. However, in the fields of anthropology and biology, these were minority positions until the mid-20th century. According to the 1950 UNESCO statement, The Race Question, an international project to debunk racist theories had been attempted in the mid-1930s. However, this project had been abandoned. Thus, in 1950, UNESCO declared that it had resumed:
up again, after a lapse of fifteen years, a project which the International Institute for Intellectual Co-operation has wished to carry through but which it had to abandon in deference to the appeasement policy of the pre-war period. The race question had become one of the pivots of Nazi ideology and policy. Masaryk and Beneš took the initiative of calling for a conference to re-establish in the minds and consciences of men everywhere the truth about race... Nazi propaganda was able to continue its baleful work unopposed by the authority of an international organisation.
The Third Reich's racial policies, its eugenics programs and the extermination of Jews in the Holocaust, as well as Gypsies in the Porrajmos and others minorities led to a change in opinions about scientific research into race after the war. Changes within scientific disciplines, such as the rise of the Boasian school of anthropology in the United States contributed to this shift. These theories were strongly denounced in the 1950 UNESCO statement, signed by internationally renowned scholars, and titled The Race Question.
Polygenism and racial typologies
Works such as Arthur Gobineau's An Essay on the Inequality of the Human Races (1853-1855) may be considered as one of the first theorizations of this new racism, founded on an essentialist notion of race, which opposed the former racial discourse, of Boulainvilliers for example, which saw in races a fundamentally historical reality which changed over time. Gobineau thus attempted to frame racism within the terms of biological differences among human beings, giving it the legitimacy of biology. He was one of the first theorists to postulate polygenism, stating that there were, at the origins of the world, various discrete "races." Gobineau's theories would be expanded, in France, by Georges Vacher de Lapouge (1854-1936)'s typology of races, who published in 1899 The Aryan and his Social Role, in which he claimed that the white, "Aryan race", "dolichocephalic", was opposed to the "brachycephalic" race, of whom the "Jew" was the archetype. Vacher de Lapoug thus created a hierarchical classification of races, in which he identified the "Homo europaeus (Teutonic, Protestant, etc.), the "Homo alpinus" (Auvergnat, Turkish, etc.), and finally the "Homo mediterraneus" (Neapolitan, Andalus, etc.) He assimilated races and social classes, considering that the French upper class was a representation of the Homo europaeus, while the lower class represented the Homo alpinus. Applying Galton's eugenics to his theory of races, Vacher de Lapouge's "selectionism" aimed first at achieving the annihilation of trade unionists, considered to be a "degenerate"; second, creating types of man each destined to one end, in order to prevent any contestation of labour conditions. His "anthroposociology" thus aimed at blocking social conflict by establishing a fixed, hierarchical social order
The same year than Vacher de Lapouge, William Z. Ripley used identical racial classification in The Races of Europe (1899), which would have a great influence in the United States. Others famous scientific authors include H.S. Chamberlain at the end of the 19th century (a British citizen who naturalized himself as German because of his admiration for the "Aryan race") or Madison Grant, a eugenicist and author of The Passing of the Great Race (1916).
Human Zoos (called "People Shows"), were an important means of bolstering popular racism by connecting it to scientific racism: they were both objects of public curiosity and of anthropology and anthropometry. Joice Heth, an African American slave, was displayed by P.T. Barnum in 1836, a few years after the exhibition of Saartjie Baartman, the "Hottentot Venus", in England. Such exhibitions became common in the New Imperialism period, and remained so until World War II. Carl Hagenbeck, inventor of the modern zoos, exhibited animals aside of human beings considered as "savages". Congolese pygmy Ota Benga was displayed in 1906 by eugenicist Madison Grant, head of the Bronx Zoo, as an attempt to illustrate the "missing link" between humans and orangutans: thus, racism was tied to Darwinism, creating a social Darwinism ideology which tried to ground itself in Darwin's scientific discoveries. The 1931 Paris Colonial Exhibition displayed Kanaks from New Caledonia. A "Congolese village" was on display as late as 1958 at the Brussels' World Fair.
Racism and colonialism in the nineteenth century
Second European colonization wave (19th century–20th century)
Authors such as Hannah Arendt, in her 1951 book The Origins of Totalitarianism, have said that the racist ideology ("popular racism") developed at the end of the nineteenth century helped legitimize the imperialist conquests of foreign territories, and crimes that accompanied it (such as the Herero and Namaqua Genocide, 1904-1907, or Armenian Genocide, 1915-1917). Rudyard Kipling's poem The White Man's Burden (1899) is one of the more famous illustrations of the belief in the inherent superiority of the European culture over the rest of the world, though also thought to be a satirical vantage of such imperialism. Racist ideology thus helped legitimize subjugation and the dismantling of the traditional societies of indigenous peoples, which were thus conceived as humanitarian obligations as a result of these racist beliefs.
However, during the 19th century, West European colonial powers were involved in the suppression of the Arab slave trade in Africa, as well as in suppression of the slave trade in West Africa. Other colonialists recognized the depravity of their actions but persisted for personal gain and there are some Europeans during the time period who objected to the injustices caused by colonialism and lobbied on behalf of aboriginal peoples. Thus, when the "Hottentot Venus" was displayed in England in the beginning of the nineteenth century, the African Association publicly opposed itself to the exhibition. The same year that Kipling published his poem, Joseph Conrad published Heart of Darkness (1899), a clear criticism of the Congo Free State owned by Leopold II of Belgium.
Examples of racial theories used to legitimate the imperialist conquest include the creation of the "Hamitic" ethno-linguistic group during the European exploration of Africa. Used in different ways, the term was first used by Johann Ludwig Krapf (1810-1881) to qualify all languages of Africa spoken by black people. It was then restricted by Karl Friedrich Lepsius (1810-1877) to African non-Semitic languages. The term then became quite popular, and was applied to different groups (Ethiopians, Eritreans, Berbers, Nubians, Somalis, etc.) Europeans conceived "Hamitic" people, allegedly descendants of the biblical Ham, son of Noah, as leaders within Africa.
However, the allegedly Hamitic peoples themselves were often deemed to have 'failed' as rulers, a failing that was sometimes explained by interbreeding with "non-Hamites". So, in the mid-20th century the German scholar Carl Meinhof (1857-1944) claimed that the "Bantu race" was formed by a merger of Hamitic and "Negro races". The 'Hottentots' (Nama or Khoi) were formed by the merger of Hamitic and Bushmen ("San) races" — both being termed nowadays as Khoisan peoples). The term "Hamitic" is nowadays obsolete. Racism spread throughout the "New World" in the late 19th and early 20th centuries. Whitecapping which started in Indiana in the late 19th century soon spread throughout all of North America, causing many African laborers to flee from the land they worked on.
Mainly dehumanization, but also racism, played a role in the American mutilation of Japanese war dead during World War II
Main articles: Nazism and race, Racial policy of Nazi Germany, Generalplan Ost, Eugenics in Showa Japan, Apartheid in South Africa, Racial segregation in the United States, Anti-Chinese legislation in Indonesia, and Anti-Japanese sentiment in Korea
U.S. government poster from WWII featuring a Japanese soldier depicted as a rat
State racism played a role in the Nazi Germany regime and fascist regimes in Europe, and in the first part of Japan's Showa period. State racism also played a major part in the formation of the Dominican Republic's identity  and violent actions encouraged by Dominican governmental xenophobia against Haitans and "Haitian looking" people. Currently the Dominican Republic employs a de-facto system of separatism for children and grandchildren of Haitians and black Dominicans, denying them birth certificates, education and access to health care. These governments advocated and implemented policies that were racist, xenophobic and, in case of Nazism, genocidal. The formation of the Dominican Republic was based on the Christian anti-semitism and racism carried out during the Reconquest of Spain.   
Racism in the Middle Ages and during the Renaissance
Racist opinions occurred in the works of some Persian and Arab-Muslim historians and geographers. In the 14th century CE, the Tunisian Ibn Khaldun wrote:
- :"beyond [known peoples of black West Africa] to the south there is no civilization in the proper sense. There are only humans who are closer to dumb animals than to rational beings. They live in thickets and caves, and eat herbs and unprepared grain. They frequently eat each other. They cannot be considered human beings." "Therefore, the Negro nations are, as a rule, submissive to slavery, because (Negroes) have little that is (essentially) human and possess attributes that are quite similar to those of dumb animals, as we have stated."
In the same period, the Egyptian Al-Abshibi (1388-1446) wrote, "It is said that when the [black] slave is sated, he fornicates, when he is hungry, he steals."
Richard E. Nisbett has said that the question of racial superiority may go back at least a thousand years, to the time when the Moors invaded the Iberian peninsula, occupying most of Hispania for six centuries, where they founded the advanced civilization of Al-Andalus (711-1492). Al-Andalus coincided with La Convivencia, an era of religious tolerance and with the Golden age of Jewish culture in the Iberian Peninsula (912, the rule of Abd-ar-Rahman III - 1066, Granada massacre). It was followed by a violent Reconquista under the Reyes Catolicos (Catholic Kings), Ferdinand V and Isabella I. The Catholic Spaniards then formulated the Cleanliness of blood doctrine. It was during this time in history that the Western concept of aristocratic "blue blood" emerged in a highly racialized and implicitly white supremacist context, as author Robert Lacey explains:
It was the Spaniards who gave the world the notion that an aristocrat's blood is not red but blue. The Spanish nobility started taking shape around the ninth century in classic military fashion, occupying land as warriors on horseback. They were to continue the process for more than five hundred years, clawing back sections of the peninsula from its Moorish occupiers, and a nobleman demonstrated his pedigree by holding up his sword arm to display the filigree of blue-blooded veins beneath his pale skin--proof that his birth had not been contaminated by the dark-skinned enemy. Sangre azul, blue blood, was thus a euphemism for being a white man--Spain's own particular reminder that the refined footsteps of the aristocracy through history carry the rather less refined spoor of racism.
Following the expulsion of most Sephardic Jews from the Iberian peninsula, the remaining Jews and Muslims were forced to convert to Roman Catholicism, becoming "New Christians" which were despised and discriminated by the others Christians. An Inquisition was carried out by members of the Dominican Order in order to weed out converts that still practiced Judaism and Islam in secret. The system and ideology of the limpieza de sangre ostracized Christian converts from society, regardless of their actual degree of sincerity in their faith. In Portugal, the legal distinction between New and Old Christian was only ended through a legal decree issued by the Marquis of Pombal in 1772, almost three centuries after the implementation of the racist discrimination. The limpieza de sangre doctrine was also very common in the colonization of the Americas, where it led to the racial separation of the various peoples in the colonies and created a very intricate list of nomenclature to describe one's precise race and, by consequence, one's place in society. This precise classification was described by Eduardo Galeano in the Open Veins of Latin America (1971). It included, among others terms, mestizo (50% Spaniard and 50% Native American), castizo (75% European and 25% Native American), Spaniard (87.5% European and 12.5% Native American), Mulatto (50% European and 50% African), Albarazado (43.75% Native American, 29.6875% European, and 26.5625% African), etc.
At the end of the Renaissance, the Valladolid debate (1550-1551) concerning the treatment of natives of the "New World" opposed the Dominican friar and Bishop of Chiapas Bartolomé de Las Casas to another Dominican philosopher Juan Ginés de Sepúlveda. The latter argued that "Indians" were natural slaves because they had no souls, and were therefore beneath humanity. Thus, reducing them to slavery or serfdom was in accordance with Catholic theology and natural law. To the contrary, Bartolomé de Las Casas argued that the Amerindians were free men in the natural order and deserved the same treatment as others, according to Catholic theology. It was one of the many controversy concerning racism, slavery and Eurocentrism that would arise in the following centuries.
Although anti-Semitism has a long European history, related to Christianism (anti-Judaism), racism itself is frequently described as a modern phenomenon. In the view of the French intellectual Michel Foucault, the first formulation of racism emerged in the Early Modern period as the "discourse of race struggle", a historical and political discourse which Foucault opposed to the philosophical and juridical discourse of sovereignty. Philosopher and historian Michel Foucault argued that the first appearance of racism as a social discourse (as opposed to simple xenophobia, which some might argue has existed in all places and times) may be found during the 1688 Glorious Revolution in Great Britain, in Edward Coke or John Lilburne's work.
However, this "discourse of race struggle", as interpreted by Foucault, must be distinguished from 19th century biological racism, also known as "race science" or "scientific racism". Indeed, this early modern discourse has many points of difference with modern racism. First of all, in this "discourse of race struggle", "race" is not considered a biological notion — which would divide humanity into distinct biological groups — but as a historical notion. Moreover, this discourse is opposed to the sovereign's discourse: it is used by the bourgeoisie, the people and the aristocracy as a mean of struggle against the monarchy. This discourse, which first appeared in Great Britain, was then carried on in France by people such as Boulainvilliers, Nicolas Fréret, and then, during the 1789 French Revolution, Sieyès, and afterward Augustin Thierry and Cournot. Boulainvilliers, which created the matrix of such racist discourse in medieval France, conceived the "race" as something closer to the sense of "nation", that is, in his times, the "people".
He conceived France as divided between various nations — the unified nation-state is, of course, here an anachronism — which themselves formed different "races". Boulainvilliers opposed the absolute monarchy, who tried to bypass the aristocracy by establishing a direct relationship to the Third Estate. Thus, he created this theory of the French aristocrats as being the descendants of foreign invaders, whom he called the "Franks", while the Third Estate constituted according to him the autochthonous, vanquished Gallo-Romans, who were dominated by the Frankish aristocracy as a consequence of the right of conquest. Early modern racism was opposed to nationalism and the nation-state: the Comte de Montlosier, in exile during the French Revolution, who borrowed Boulainvilliers' discourse on the "Nordic race" as being the French aristocracy that invaded the plebeian "Gauls", thus showed his despise for the Third Estate calling it "this new people born of slaves... mixture of all races and of all times".
While 19th century racism became closely intertwined with nationalism, leading to the ethnic nationalist discourse which identified the "race" to the "folk", leading to such movements as pan-Germanism, Zionism, pan-Turkism, pan-Arabism, and pan-Slavism, medieval racism precisely divided the nation into various non-biological "races", which were thought as the consequences of historical conquests and social conflicts. Michel Foucault traced the genealogy of modern racism to this medieval "historical and political discourse of race struggle". According to him, it divided itself in the 19th century according to two rival lines: on one hand, it was incorporated by racists, biologists and eugenicists, who gave it the modern sense of "race" and, even more, transformed this popular discourse into a "state racism" (e.g. Nazism). On the other hand, Marxists also seized this discourse founded on the assumption of a political struggle which provided the real engine of history and continued to act underneath the apparent peace. Thus, Marxists transformed the essentialist notion of "race" into the historical notion of "class struggle", defined by socially structured position: capitalist or proletarian. In The Will to Knowledge (1976), Foucault analyzed another opponent of the "race struggle" discourse: Sigmund Freud's psychoanalysis, which opposed the concepts of "blood heredity," prevailent in the 19th century racist discourse.
During the Age of Enlightenment
While modern racism has an essentialist and biological conception of race, racist or xenophobic opinions have been shared by some authors, from the Antiquity to the Age of Enlightenment. However, this early form of racism did not conceive of "race" as a biological concept — as biology itself did not exist as such —, but as the accidental effect of climate on physical traits. With the Age of Discovery, the diversity of mankind became an important topic of research, leading to debates concerning monogenism and polygenism, respectively endorsing the unique origin of mankind (coherent with the Genesis Biblical account) and the multiple origins of mankind. Pierre de Maupertuis (1698-1759), for example, reconciled the Biblical account with the present diversity of "races" in his Essai de philosophie morale (1749, Essay on Moral Philosophy), explaining "racial" differences by climatic factors. He thus explained the colour of black people through the inheritance of acquired characteristics, claiming white was the original colour of mankind. He also highlighted the spiritual strength of Africans seized as slaves, pointing out how, like the Ancient Stoic philosophers, they prefer to die rather than to survive to capture. Arguments on the influence of climate found additional weight with Buffon's Histoire naturelle in the middle of the 18th century, and his thesis on the unity of mankind was taken back by Diderot and d'Alembert's Encyclopédie in the article Humaine, espèce (Human, Specie). According to Ann Thomson, although Buffon did establish a "clear hierarchy [...] between the beautiful white civilised races of the temperate zone and those savages who have degenerated in more extreme climates, his emphasis on the unity of the human race and his distinction between humans and other animals were extremely influential." The abolitionists thus used his arguments to show that Africans were not naturally inferior, and could be improved by different treatment and different climate. 
The abbé Demanet (1767) claimed that a Portuguese colony in Africa had become black after several generations, due to the effect of climate, a story which was given wide credence by abolitionists, quoted for example by Cabanis (1757-1808) andThomas Clarkson (1760-1846) The abolitionist Physiocrat abbé Pierre-Joseph-André Roubaud alleged that black Africans would change skin colour if they lived in different climatic conditions. According to Ann Thomson,
What emerges from these examples is the overwhelming desire to insist on the unity of the human race by emphasizing the effect of the climate and other environmental causes, but not necessarily to claim the equality of all humans; for the existence of a hierarchy is not systematically denied but, on the contrary, frequently accepted [exceptions quoted by Thomson includes James Dunbar and the abbé Grégoire.]. This of course was to have long-lasting effects in the Nineteenth Century, when the arguments about climate were countered and the hierarchy was seen to be permanent, as the differences between humans were innate. 
Moral factors were also considered to influence physical and psychical traits. The American abolitionist Anthony Benezet stated, in the Historical Account of Guinea (1772), that Africans in Africa were a sociable, virtuous and intelligent people; but that their servile condition in Amercia explained their "degeneration" and adoption of the vices of Europeans. Furthermore, the theory of the Great Chain of Being, which asserted a continuity between animals and humans, thus contradicting Christian religion (and henceforth supported by materialists such as Diderot) was used by some, such as Edward Long, spokesman for the West India Lobby, or Charles White’s Account of the Regular Gradation in Man (1799 — White denied the effect of climate) to assert the animal nature of some humans.
Inter-minority racism is sometimes considered controversial because of theories of power in society. Prejudiced thinking among and between minority groups does occur, for example conflicts between blacks and Korean Americans (notably in the 1992 Los Angeles Riots), between blacks and Jews (such as the riots in Crown Heights in 1991), between new immigrant groups (such as Latinos), or towards whites.    
There has been a long-running racial tension between African Americans and Mexican Americans.    There have been several significant riots in California prisons where Mexican American inmates and African Americans have targeted each other particularly, based on racial reasons. There have been reports of racially motivated attacks against African Americans who have moved into neighborhoods occupied mostly by Mexican Americans, and vice versa. There had also been cases in the late 1920's California in which Filipino immigrants have been victimized for moving into a predominantly white neighborhood, or for working in an overwhelmingly white workplace. Recently there has also been an increase in racial violence between whites and Hispanic immigrants and between African immigrants and American blacks.
The Aztlan movement has been described as racist. The movement's goal involves the pursuit of repossessing the American southwest. It has also been called the Mexican "reconquista"(re-conquest) whose name was inspired by the Spanish "reconquista" which led to the expulsion of the Moors from Spain. According to gang experts and law enforcement agents, a longstanding race war between the Mexican Mafia and the Black Guerilla family, a rival African American prison gang, has generated such intense racial hatred among Mexican Mafia leaders, or shot callers, that they have issued a "green light" on all blacks. A sort of gang-life fatwah, this amounts to a standing authorization for Latino gang members to prove their mettle by terrorizing or even murdering any blacks sighted in a neighborhood claimed by a gang loyal to the Mexican Mafia. 
In Britain, tensions between minority groups can be just as strong as any minority group suffers with the majority population. In Birmingham, there have been long-term divisions between the Black and South Asian communities, which were illustrated in the Handsworth riots and in the smaller 2005 Birmingham riots. Tensions between Muslims and Sikhs - two groups who have a history of bad relations - have flared in Slough and at some colleges to the west of London. In Dewsbury, a Yorkshire town with a relatively high Muslim population, there have been tensions and minor civil disturbances between Kurds and South Asians. 
During the Congo Civil War (1998-2003), Pygmies were hunted down like game animals and eaten. Both sides of the war regarded them as "subhuman" and some say their flesh can confer magical powers. UN human rights activists reported in 2003 that rebels had carried out acts of cannibalism. Sinafasi Makelo, a representative of Mbuti pygmies, has asked the UN Security Council to recognise cannibalism as a crime against humanity and an act of genocide. 
^ UN International
Convention on the Elimination of All of Racial Discrimination, NEW YORK
7 March 1966
(1994). 'The Invention of the White Race: Volume 1 London, UK: Verso.