Green’s Dictionary of Slang

a street clown (with no racial inference); a black minstrel; also attrib.

1841		in N. Hawthorne Amer. Notebooks (1932) 78: A company of fantastic figures, arranged in a ring for a dance [...] an Indian squaw, a negro of the Jim Crow order.
1859, 1860		Hotten Dict. of Modern Sl. etc.
1861		(con. 1840s–50s) H. Mayhew London Labour and London Poor III 119/2: I got acquainted, too, with singing people, [...] and came out at last on my own account in the streets, in the Jim Crow line.
1864, 1867, 1870		Hotten Sl. Dict.
1899		A. Binstead Houndsditch Day by Day 175: The James Crow aristocracy of the dramatic profession patronised him liberally.