I heard the he was some famous guy, and was wondering if this was a coincidence, or on purpose. If so, are their more well known rivals, Jessie and James, based of some famous 19th century person too?
Butch Cassidy was an well known outlaw in the 1900's, and yes, they were based off him:
Butch Cassidy
Jessie and James were based off Jessie James, another American outlaw:
Jessie James