Non-scientific notion of race

The 19th-century notion that humankind can be divided into discrete races has now been abandoned by geneticists and historians alike.

(John Parker & Richard Bathbone, African History: A Very Short Introduction, Oxford University Press, 2007, p. 9)

I can see how geneticists may have abandoned the notion, but historians? The notion of race would still seem to play a major role in American history and politics. Perhaps it may not have been entirely abandoned in other parts of the world, either.