Green’s Dictionary of Slang

(US) bigoted against or segregated from black people.

1903		N.Y. Times 23 Sept. n.p.: The report that the President was seeking reconciliation with the ‘Lilywhite’ faction, which eliminated the negro from the last State Convention [DA].
1920		Ade Hand-made Fables 72: Among the Managers of the Party Machine were many Ex-Barkeeps, former Poker Players, perjuring Tax Dodgers, and amateur High Binders who had been waiting for years to take a Punch at the lilywhite Samaritan.
1932		‘R. Scully’ Scarlet Pansy 166: Now, in Atlantic City, the icemen are all colored [...] Nevertheless, all the famous ones of Philadelphia, and many of those from New York, white, lily-white indeed, attend the function.
1949		(ref. to 1929) W. White A Man Called White 104: His attitude to Negroes caused me to coin a phrase which gained considerable currency, particularly in the Negro world, in which I described Hoover as ‘the man in the lily-White House’.
1952		Lait & Mortimer USA Confidential 115: Minnesota, until recently lily-white, is swarming with tens of thousands of more recently arrived darkish emigres from the deep South.
1967		R. Conot Rivers of Blood 164: [M]ayor of a lilywhite suburban town.
1970		J. Conaway Big Easy 119: You mean your great big ole lily-white liberal heart was just a-flopping over with concern for us bloods.
1977		(con. 1960s) D. Goines Black Gangster (1991) 99: We can [...] put an end to discrimination in some of these lilywhite bars and clubs.
1994		(con. 1941) A. Kernan Crossing the Line 87: It was a lily-white navy that never gave its racism a thought.
2000		T. Udo Vatican Bloodbath 52: M had assassinated both of them to spare their lily-white English throne from the stain of a brown Arab baby.
2020		C. Hiaasen Squeeze Me 110: ‘[It’s] the lily-whitest place I’ve ever worked. Practically everyone’s on visas from the Eastern bloc’.