Green’s Dictionary of Slang

(US) an important, powerful man.

1897		A.H. Lewis Wolfville 101: I takes it you’re the old he-coon of this yere outfit?
1925		Liberty 14 Nov. 45: Hey!...Who’s the he-coon around here? [HDAS].
1955		W. Henry Who Rides with Wyatt 75: Frank Patterson and the old he-coon himself.
1971		CBS Eve. News 4 Nov. [CBS-TV] Bob Sykes, known as the ‘he-coon of the First District’ [HDAS].