He probably got the Medal of Honor just for being in command at the Battle of the Teton River. (The U.S. was so desperate for heroes by the end of the Second Mexican War that I would imagine both him and TR earned a MoH there, and Custer did lead from the front in that battle so there would be justification for giving him an award for valor.) Maybe a Remembrance Cross for the Barrel Roll Offensive. This would be much less justified since Custer wasn't personally in harms way during the fighting, but it was a big enough victory to earn him a fourth star, so it probably would get him a major decoration as well, and it's not exactly unheard of for the U.S. War Department to bend the rules regarding medals for gallantry to the breaking point when honoring a high ranking general (witness Douglas MacArthur IOTL earning a Medal of Honor for his defense of the Philippines.) If the US in TL-191 created something akin to the Distinguished Service Medal then Custer would certainly have been one of the first recipients of that medal as well just by virtue of his rank, celebrity, and length of service. There's also probably some sort of specific victory medal for the First Great War in addition to the war's campaign medal, and maybe some sort of Army of Occupation medal for his post-war service in occupied Canada. He could also have picked up a Bronze Star for his actions following MacGregor's first bombing attempt against him.
Definitely. Dowling noted that Custer on his final tour wasn't even pretending to follow the uniform regulations anymore and described him as looking "something like a South American emperor, something like God on a particularly tasteless afternoon."
The image of Field Marshall Roberts might be a good start though it is lacking a suitably grandiose hat.
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