1932 (as an adjective from 1938), from race (n.2) + -ist. Racism (q.v.) is in use by 1928, originally in the context of fascist theories, and common from 1936. These words replaced earlier racialism (1882) and racialist (1910), both often used early 20c. in a British or South African context. There are isolated uses of racism from c. 1900.
Returning recently from a six months' visit to Europe, the Rev. John LaFarge, noted Catholic writer, warned at a dinner given in his honor that the destructive forces of "racism" are increasing in the United States, and that they could cause irreparable harm among the American people if immediate steps are not taken to combat them.
Father LaFarge said that American racism is directed principally against Negroes, Jews, and foreigners. He described it as "the pale but venomous cousin" of Nazi racism. Like its Nazi counterpart, he added, it has erected impassable barriers between extensive regions and large groups of people, has formed its own myths and moulded its own social institutions, and above all has come consistently into conflict with Christian teachings. [Opportunity, Journal of Negro Life, vol. XVII, No. 2, Feb. 1939]
In the U.S., race hatred, race prejudice had been used, and, especially in 19c. political contexts, negrophobia. Anglo-Saxonism as "belief in the superiority of the English race" had been used (disparagingly) from 1860. Anti-Negro (adj.) is attested in British and American English from 1819.