1831, originally Southern U.S. black slang.
The slaves themselves entertain the very highest contempt for white servants, whom they designate as 'poor white trash.' [Fanny Kemble, journal, Jan. 6, 1833]
(also white-shoe) Having the attitudes, appearance, etc, of the Ivy League: Do I look white shoe?/ a Harvard-educated bluestocking who practiced white-shoe corporate lawnoun phrase
A typical Ivy League student
[1980s+; fr the white buckskin shoes that were part of that student's dress]