White supremacy is the belief that white people are superior to those of other races. The belief favors the maintenance and defense of any power and privilege held by white people. White supremacy has roots in the now-discredited doctrine of scientific racism and was a key justification for European colonialism."Ostensibly scientific": cf. Theodore M. Porter, Dorothy Ross (eds.) 2003. The Cambridge History of Science: Volume 7, The Modern Social Sciences Cambridge University Press, p. 293 "Race has long played a powerful popular role in explaining social and cultural traits, often in ostensibly scientific terms"; Adam Kuper, Jessica Kuper (eds.), The Social Science Encyclopedia (1996), "Racism", p. 716: "This [sc. scientific] racism entailed the use of 'scientific techniques', to sanction the belief in European and American racial Superiority"; Routledge Encyclopedia of Philosophy: Questions to Sociobiology (1998), "Race, theories of", p. 18: "Its exponents [sc. of scientific racism] tended to equate race with species and claimed that it constituted a scientific explanation of human history"; Terry Jay Ellingson, The myth of the noble savage (2001), 147ff. "In scientific racism, the racism was never very scientific; nor, it could at least be argued, was whatever met the qualifications of actual science ever very racist" (p. 151); Paul A. Erickson, Liam D. Murphy, A History of Anthropological Theory (2008), p. 152: "Scientific racism: Improper or incorrect science that actively or passively supports racism".

As a political ideology, it imposes and maintains cultural, social, political, historical or institutional domination by white people and non-white supporters. In the past, this ideology had been put into effect through socioeconomic and legal structures such as the Atlantic slave trade, European colonial labor and social practices, the Scramble for Africa, Jim Crow laws in the United States, the activities of the Native Land Court in New Zealand, the White Australia policies from the 1890s to the mid-1970s, and apartheid in South Africa. This ideology is also today present among neo-Confederates.

White supremacy underlies a spectrum of contemporary movements including white nationalism, white separatism, neo-Nazism, and the Christian Identity movement. In the United States, white supremacy is primarily associated with Aryan Nations, White Aryan Resistance, and the Ku Klux Klan. The Proud Boys are considered an implicitly white supremacist organization, despite denying their association with white supremacy. In recent years, websites such as X (formerly Twitter) and Stormfront have contributed to an increased activity and interest in white supremacy.

Not all white-supremacist organizations have the same objectives, and while some may uphold a Nordicist ideal of whiteness, others are more broadly white supremacist, including members of Southern European and Eastern European descent. Different groups of white supremacists identify various racial, ethnic, religious, and other enemies, most commonly those of Sub-Saharan African ancestry, Indigenous peoples, people of Asian descent, multiracial people, Middle Eastern and North African people, Jews, Muslims, and LGBTQ+ people.

In academic usage, particularly in critical race theory or intersectionality, "white supremacy" also refers to a social system in which white people enjoy structural advantages (privilege) over other ethnic groups, on both a collective and individual level, despite formal legal equality.

History White supremacy has ideological foundations that date back to 18th-century scientific racism, the predominant paradigm of human variation that shaped international relations and racial policy from the latter part of the Age of Enlightenment until the late 20th century.

United States

Early history White supremacy was dominant in the United States both before and after the American Civil War, and it persisted for decades after the Reconstruction era. The Virginia Slave Codes of 1705 socially segregated white colonists from black enslaved persons, making them disparate groups and hindering their ability to unite. Unity of the commoners was a perceived fear of the Virginian planter gentry, who wished to prevent repeated events such as Bacon's Rebellion, occurring 29 years prior. Prior to the Civil War, many wealthy white Southerners owned slaves; they tried to justify their economic exploitation of black people by creating a "scientific" theory of white superiority and black inferiority. One such slave owner, future president Thomas Jefferson, wrote in 1785 that blacks were "inferior to the whites in the endowments of body and mind."Paul Finkelman (November 12, 2012). "The Monster of Monticello" . The New York Times. Retrieved July 14, 2020. In the antebellum South, four million slaves were denied freedom. The outbreak of the Civil War saw the desire to uphold white supremacy being cited as a cause for state secessionA Declaration of the Causes which Impel the State of Texas to Secede from the Federal Union : "We hold as undeniable truths that the governments of the various States, and of the confederacy itself, were established exclusively by the white race, for themselves and their posterity; that the African race had no agency in their establishment; that they were rightfully held and regarded as an inferior and dependent race, and in that condition only could their existence in this country be rendered beneficial or tolerable. That in this free government all white men are and of right ought to be entitled to equal civil and political rights; that the servitude of the African race, as existing in these States, is mutually beneficial to both bond and free, and is abundantly authorized and justified by the experience of mankind, and the revealed will of the Almighty Creator, as recognized by all Christian nations; while the destruction of the existing relations between the two races, as advocated by our sectional enemies, would bring inevitable calamities upon both and desolation upon the fifteen slave-holding states." and the formation of the Confederate States of America.The controversial "Cornerstone Speech", Alexander H. Stephens (Vice President of the Confederate States), March 21, 1861, Savannah, Georgia : "Our new government is founded upon exactly the opposite idea; its foundations are laid, its cornerstone rests, upon the great truth that the negro is not equal to the white man; that slavery—subordination to the superior race—is his natural and normal condition."

Native Americans had been dehumanized as "merciless Indian savages" in the United States Declaration of Independence, and in Martin Luther King Jr.'s 1964 book Why We Can't Wait he wrote: "Our nation was born in genocide when it embraced the doctrine that the original American, the Indian, was an inferior race." Two sculptures reflecting the view of the Natives espoused in the declaration were commissioned by the U.S. government and stood outside the U.S. Capitol from 1844 to 1958: The Discovery of America, which depicted a triumphant Columbus and a "female savage" according to the Pennsylvania senator James Buchanan who proposed the sculpture,Congressional Globe, April 28, 1836, p. 1316. and The Rescue, whose sculptor Horatio Greenough wrote that it was "to convey the idea of the triumph of the whites over the savage tribes".Boime, Albert (2004), A Social History of Modern Art, Volume 2: Art in an Age of Counterrevolution, 1815–1848, (Series: Social History of Modern Art); University of Chicago Press, p. 527. In an 1890 editorial about the Natives and the American Indian Wars, author L. Frank Baum wrote: "The Whites, by law of conquest, by justice of civilization, are masters of the American continent, and the best safety of the frontier settlements will be secured by the total annihilation of the few remaining Indians." Full text of both, with commentary by professor A. Waller Hastings

The Naturalization Act of 1790 limited U.S. citizenship to whites only. In some parts of the United States, many people who were considered non-white were disenfranchised, barred from government office, and prevented from holding most government jobs well into the second half of the 20th century. Professor Leland T. Saito of the University of Southern California writes: "Throughout the history of the United States, race has been used by whites for legitimizing and creating difference and social, economic and political exclusion."Leland T. Saito (1998). "Race and Politics: Asian Americans, Latinos, and Whites in a Los Angeles Suburb". p. 154. University of Illinois Press

19th century

A belief in racial purity and white supremacy were among the reasons for the anti-miscegenation laws in the U.S, with Abraham Lincoln stating in an 1858 speech, "I am not, nor ever have been in favor of making voters or jurors of negroes, nor of qualifying them to hold office, nor to intermarry with white people. I as much as any man am in favor of the superior position assigned to the white race." By the late 1800s, 38 U.S. states had laws banning interracial marriage.

Benjamin Tillman was a white supremacist former U.S. governor and senator who participated and boasted about the lynchings of Black Americans, and defended on the floor of the U.S. Senate. Rebecca Latimer Felton, a white supremacist and the first woman to serve in the U.S. Senate, gave a speech calling for the lynching of Black men.

20th century A series of U.S politicians continued to advocate and agitate towards White supremacy. An example being an Elected Governor of Mississippi, James K. Vardaman, who used the term White Supremacy verbatim when he said "If it is necessary every Negro in the state will be lynched; it will be done to maintain white supremacy."

Eugene Talmadge was a white supremacist who was elected four times as the governor of Georgia. His opponent, Ellis Gibbs Arnall, once noted that nobody could beat Talmadge in what he cynically called the "nigger-hating contest". Both were white supremacists and anti-black, but Arnall was less crude about it.

The denial of social and political freedom to minorities continued into the mid-20th century, resulting in the civil rights movement. The movement was spurred by the lynching of Emmett Till, a 14-year-old boy. David Jackson writes it was the image of the "murdered child's ravaged body, that forced the world to reckon with the brutality of American racism."

Sociologist Stephen Klineberg has stated that U.S. immigration laws prior to 1965 clearly "declared that Northern Europeans are a superior subspecies of the white race". The Immigration and Nationality Act of 1965 opened entry to the U.S. to non-Germanic groups, and significantly altered the demographic mix in the U.S. as a result. The last 16 states in which interracial marriage was banned had such laws in place until 1967 when they were invalidated by the Supreme Court of the United States' decision in Loving v. Virginia.Warren, Earl. Majority opinion. Loving v. Virginia. Documents of American Constitutional and Legal History, edited by Urofsky and Finkelman, Oxford UP, 2002, p. 779. These mid-century gains had a major impact on white Americans' political views; segregation and white racial superiority, which had been publicly endorsed in the 1940s, became minority views within the white community by the mid-1970s, and continued to decline in 1990s' polls to a single-digit percentage. For sociologist Howard Winant, these shifts marked the end of "monolithic white supremacy" in the United States.