Thus the Comte de Montlosier, in exile during the French Revolution, equated class difference in 18th-century France with racial difference. in 1863, and the etymology of the word is tied up with political conflicts during the American Civil War over the abolition of slavery and over the racial segregation of African-Americans.
Borrowing Boulainvilliers' discourse on the "Nordic race" as being the French aristocracy that invaded the plebeian "Gauls", he showed his contempt for the lowest social class, the Third Estate, calling it "this new people born of slaves ... Miscegenation comes from the Latin miscere, "to mix" and genus, "kind". The reference to genus was made to emphasize the supposedly distinct biological differences between whites and non-whites, though all humans belong to the same genus, Homo, and the same species, Homo sapiens.
By then, the word miscegenation had entered the common language of the day as a popular buzzword in political and social discourse.
The issue of miscegenation, raised by the opponents of Abraham Lincoln, featured prominently in the election campaign of 1864.
The term's historical use in contexts that typically implied disapproval is also a reason why more unambiguously neutral terms such as interracial, interethnic or cross-cultural are more common in contemporary usage.
In Spanish, Portuguese, and French, the words used to describe the mixing of races are mestizaje, mestiçagem and métissage.
The Nazi ban on interracial sexual relations and marriages was enacted in September 1935 as part of the Nuremberg Laws, the Gesetz zum Schutze des deutschen Blutes und der deutschen Ehre (The Law for the Protection of German Blood and German Honour).
The Nuremberg Laws classified Jews as a race, and forbade extramarital sexual relations and marriage between persons classified as "Aryan" and "non-Aryan".
Before the publication of Miscegenation, the word amalgamation, borrowed from metallurgy, had been in use as a general term for ethnic and racial intermixing.
Today, the mixes among races and ethnicities are diverse, so it is considered preferable to use the term "mixed-race" or simply "mixed" (mezcla).
In Portuguese-speaking Latin America (i.e., Brazil), a milder form of caste system existed, although it also provided for legal and social discrimination among individuals belonging to different races, since slavery for blacks existed until the late 19th century.
A contemporary usage of this metaphor was that of Ralph Waldo Emerson's private vision in 1845 of America as an ethnic and racial smelting-pot, a variation on the concept of the melting pot. S on the desirability of such intermixing, including that between white Protestants and Irish Catholic immigrants, were divided.
The term miscegenation was coined to refer specifically to the intermarriage of blacks and whites, with the intent of galvanising opposition to the war. states, as well as laws in South Africa, also banned sexual relations between such individuals.