Brian Downey did some interesting Wilsonology recently which raised the matter of James H. Wilson knocking about Antietam battlefield after the battle. I thought I had written about this at length here but I have not. Just posted a reference in this snippet.
Brian had to deduce which aide named Wilson should be attributed to a quote printed by Sears and I think he has hit on the right one. H.
Back to confusion, however. Brian also had to decide which general JHW was assigned to in the post-Antietam anecdote. In an end-of-life memoir, Wilson said he was on Mac's staff and Brian goes with that.
However, IIRC, in Grant's Cavalryman: The Life and Wars of General James H. Wilson, author Longacre has Wilson accompanying John A. McClernand around Antietam as McClernand's current aide and as a McClellan former aide.
Wilson's self-appointed task on tour with McClernand was to effect a switch; he played the middleman role trying to convince GBM to follow McClernand out West as the commander of the combined forces against Vicksburg. He says he told McClellan that Sherman and Grant would never agree to serve under McClernand but all three would willingly follow McClellan.
This story is obliquely confirmed in an article by Darius Couch published in Battles and Leaders.
I'll dig out some books and make a proper posting on McClellan for Vicksburg and J.H. Wilson's role in that scheme.
Of the various James Wilsons serving as aides, BTW, James H. Wilson could be called "the gay one." As Grant historian Brooks Simpson has pointed out (scroll down link to comments), Wilson and Grant aide Adam Badeau were lovers. Brooks mentions their sexy correspondence in Princeton's Firestone Library; part of it was published in 1966 (see card 211). Longacre actually calls Badeau "prissy."
Wilson's gayness has not made it into Wikipedia yet. His wife's death is also not entirely without interest.
There is more Wilsonia available (it seems) than historians care to bother with.