Butch ended up running lots of stolen stock into the badlands of Bryce Canyon, into the stony wilderness of the Robbers' Roost, and beyond – into southwestern Colorado, through the tough cow towns of Mancos and Dolores and Cortez. Under Mike Cassidy's tutelage, he learned to ride bareback, rope steers, plant a hot brand, and handle guns. He learned the fast draw and how to make a standing leap into a moving saddle.
He soon drifted into Wyoming, Montana, and Nebraska, cowpunching on ranches for a meager living, and by 1889 he was in the mining boomtown of Telluride, Colorado. There he trained horses, hauled ore in treacherous horse trains, and became known as a skilled jockey in the horse-racing and gambling rackets that were the chief entertainment of cowboys. According to Charles Kelly, he was a well-built and charming young man, with "a disarming smile" and a "rapid-fire way of talking, which later served him well." He was "universally liked" and known across Utah as "the best shot in Circle Valley," this despite the fact that we are told in varying accounts that he abhorred bloodshed, was "never vengeful," "was quiet and inoffensive," and "cared not at all for liquor or cards."
In Telluride, he met a horse-racing buff and cattle rustler named Matt Warner, who one day persuaded him to fire a tremendously powerful gun while seated on a horse-watering trough. The gun – which Warner had, for reasons lost to history, nicknamed Butch – knocked young Cassidy flat into the water in the trough. To honor the occasion, he took the name of the gun, and Butch Cassidy was born.
Butch's first large robbery that we know of, in 1889, netted $21,000 from the San Miguel Valley Bank in Telluride, which he took down with Warner and two criminal associates. Chased by the law, he headed for the Outlaw Trail, fleeing west to Utah and then forcing his horse on a grueling 200-mile ride north toward the Wyoming border. After a rest of just three days, he doubled back, heading to the safety of the Robbers' Roost, which was already well established as a hideout for horse thieves and murderers.
By 1896, after having been caught near Lander, Wyoming, and then doing two years in state prison for horse theft, Butch had formed around him the core of veteran robbers and bad men who would eventually come to be known as the Wild Bunch – and sometimes as the Hole-in-the-Wall Gang and sometimes as the Train Robbers' Syndicate. It was a loosely run outfit. "There was no compulsory drafting of men into projects," writes historian Michael Rutter. "You worked if it suited you and you liked the job." Along with Matt Warner, Cassidy's band included William Ellsworth "Elzy" Lay, a cowboy intellectual who is said to have read history by firelight, and with whom Butch planned and executed some of his most difficult robberies; William "News" Carver, a sometime member of the murderous "Black Jack" Ketchum Gang, who enjoyed seeing his name in print; and Harvey "Kid Curry" Logan, described in most accounts as a cold-blooded murderer who was more feared than Butch Cassidy.
Somewhere along the way, Butch met up with a transplanted easterner from outside Philadelphia named Harry Alonzo Longabaugh, who had studied Shakespeare as a teenager and come west at age 15. In 1887, Longabaugh faced 18 months in jail in Sundance, Wyoming, after being charged with stealing a gun, a saddle, and a horse. He wrote a letter to the local paper "to set my case before the public in a true light....I have always worked for an honest living," said the man who would come to be known as the Sundance Kid, "but having got discharged last winter, went to the Black Hills to seek employment – which I could not get....After this my course of outlawry commenced." (The friendship between Butch and Sundance was exaggerated; most researchers agree that they committed, at most, three robberies together.)
And so began the short, sweet heyday of the Wild Bunch. In August 1896, Butch and Elzy Lay hit the Bank of Montpelier in Montpelier, Idaho, for $7,165 in cash, gold, and silver. A posse chased them for a week, giving up only after the outlaws vanished into the desert. In April 1897, they snatched at least $8,000 from the mine payroll at Castle Gate, Utah. 'The Salt Lake Tribune' declared the robbery – mounted by Butch and Elzy in broad daylight, in a narrow canyon settlement with only one point of egress – "one of the most daring affairs ever recorded." Butch holed up with his haul for three months in the Robbers' Roost, where he was now considered, as Kelly writes, "king of the Roosters, an aristocrat among mere cattle rustlers." When supplies ran low, Butch dispatched his women – hookers for the most part – to the lonely towns nearby for booze and bullets, sending them across miles of hard, waterless desert. Butch lived well in the Roost: He built tents and held big barbecues, all-night gambling sessions, pistol competitions, and horse races.
Between 1897 and 1900, Butch led or helped plan nearly a dozen major bank and train holdups. The assaults on the express-car caches of the Union Pacific Corporation made him infamous nationwide. 'The New York Herald', in 1899, described him as the leader of "lawless men who have lived long in the crags and become like eagles." He was hunted by U.S. Marshals, the Pinkerton Detective Agency, and Union Pacific mercenaries. Over the 10 years it was active, the Wild Bunch made off with roughly $200,000, the equivalent today of more than $4 million. They also committed at least 20 homicides, though Butch was never implicated in pulling the trigger. "I never robbed an individual – only banks and railroads that have been robbing the people for years," Butch told a lawyer friend in 1899. Charley Gibbons, owner of a general store in the Utah village of Hanksville during the 1890s, said Butch always paid his debts and "always paid cash." Kelly, in 'The Outlaw Trail,' wrote "all old-timers interviewed for this biography, including the officers who hunted him, were unanimous in saying, 'Butch Cassidy was one of the finest men I ever knew.'" Butch was Robin Hood with a Colt .45, and enough sources attest to his decency streak that it might even be true.