I do believe his is a cavalryman; and a Federal one; and I also do not believe he is an officer, but enlisted. The presence of riding sabre, forage cap and trousers together seem to testify to that. His jacket is peculiar; with standard larger button size, it's appearance is very much like a frock coat with the lower half removed. His standing collar has small buttons on it, which tells us the collar is not intended to be worn down. Like a frock coat or shell jacket, the cuffs also have (a) the classic chevron piping, and (b) the smaller buttons like the collar.
Since this jacket is more unusual and unique the longer we look at it, I have a theory. This jacket could be custom made. There is a misconception that, with burgeoning industrial might, the North went to war in perfectly standardized uniforms, while the ill-equipped Southern armies wore a patchwork quilt of homespun, factory made, imported, and "hand-sewn-by-loved-ones" uniforms. But uniform distribution early on in the war was much like Covid vaccines now; there were shortages in some areas, while other locales enjoyed massive stockpiles; different companies produced different quality goods, and such quality could sometimes be seen at a glance; and in reality, not every Northern soldier had a cookie-cutter look. Even General Custer, also a Cavalryman, had a custom-made jacket, which was shortened for riding--much like the one we see here.
Even if this theory was to be pursued, there are questions we do not know. Is this really a custom jacket, commissioned out of personal taste, or did he improvise out of a distribution shortage in his area around the time this photograph was taken?
Anyway, cool photo! (You know, if he showed up to a re-enactment, everyone would tell him "those buttons? they're inaccurate..."
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