Hypodescent

In societies that regard some races of people as dominant or superior and others as subordinate or inferior, hypodescent is the automatic assignment of children of a mixed union or mating between members of different socioeconomic groups or ethnic groups to the subordinate group. The opposite practice is hyperdescent, in which children are assigned to the race that is considered dominant or superior.

Parallel practices include patrilineality, matrilineality and cognatic descent, which assign race according to the father, mother, or some combination, without regard to the race of the other parent. These systems may not be mutually exclusive with hypo- and hyper-descent, since either parent (or both) might be of mixed race.

Attempts to limit (or eliminate) mixed-race populations by legal means are detailed in Anti-miscegenation laws and Anti-miscegenation laws in the United States.

While customs, practices and systems of belief emphasising the value of purity of descent are arguably as old as mankind few societies systematically codified them, or legally enforced their outcome, the effect being more at the level of communal behaviour. Such was the case in classical Greece – which made clear distinctions between Greeks and Barbarians – as distinct from the Roman Republic which despite being expansionist, militarily and culturally aggressive actively encouraged the Romanisation of client kingdoms, which included making their elite citizens of Rome as reward and as exemplars.

Joseph Arthur, Comte de Gobineau (14 July 1816 – 13 October 1882) a French aristocrat, novelist and man of letters famous for developing the theory of the Aryan master race is credited as being the father of modern racial demography. His work An Essay on the Inequality of the Human Races proposed the superiority the Aryan race and lobbied for cultural and racial purity. Together with Houston Stewart Chamberlain (9 September 1855 – 9 January 1927), an English-born German author whose works presaged völkischen antisemitism, is considered an early exponent of scientific racism. Gobineau's contemporary Madison Grant (November 19, 1865 – May 30, 1937) published The Passing of the Great Race in 1916. In this work he lamented the perceived decline in 'racial hygiene' caused by increasing levels of immigration from Southern and Eastern Europe (as opposed to Western and Northern Europe) citing the 'racial history' of Europe as evidence and argument that race is the basis of civilization.

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