So, I have been searching all night for this guy, but I remember him from my American History test in college. I can't remember him for the life of me, though.
Basically, from what I remember, he lost an election and immediately went West to start a new nation to then turn around and attack the then burgeoning USA. I remember it by the name of something like "Xxxx's Rebellion" or something.
Am I hallucinating or misremembering something? Maybe I'm combining facts about the whole Hamilton 1800 election. If not, though, I'd love to refresh my memory.
I think, though I may be mistaken, that you’re talking about Aaron Burr, and some his adventures after Hamilton made him lose the 1800 election. /u/SheldonNovick goes into it a bit in this older post, though more can be said if anyone has anything else to add.