Born Robert LeRoy Park in 1866 in Beaver, Utah, the man became “Butch,” a shortened version of “Butcher,” when he worked as one in Rock Springs Wyoming. The Cassidy he picked up from a friend and mentor who had that last name.
Cassidy and three “Wild Bunch” compatriots robbed the Montpelier bank on August 13, 1896, not long after he was released from prison in Wyoming where he served 18 months for stealing horses. They got away with somewhere between $5,000 and $15,000. His equally infamous sidekick, Harry Alonzo Longabaugh, better known as “The Sundance Kid,” would join the gang shortly after the Montpelier robbery.
The bank where the robbery took place was purchased and turned into a museum in 2016 by Radk Konarik. The Bank of Montpelier was the first bank chartered in the State of Idaho, opening its doors in 1891. As a museum it is now open during the summer, welcoming several thousand visitors each year who want to see the last standing bank that Butch Cassidy robbed.
Cassidy and Sundance were both killed in a shootout with the Bolivian Army in 1908, as depicted in the 1969 movie Butch Cassidy and the Sundance Kid. Unless they weren’t. There are many stories that say they came back to the States after their South American adventure and lived quiet lives. You can start chasing those down for fun on the Butch Cassidy Wikipedia page.