The winter that Fitzpatrick arrived in St. Louis William Henry Ashley was in the process of gathering a party to make a fur trapping expedition up the Missouri River to Yellowstone Country. Ashley had advertised for young men, single, and of stout body and bold courage to join his party. Thomas was a prime specimen and joined up.
As to the list of the other young men who joined Ashley on this adventure, it reads like a future whose-who of the famous, though not so rich in most cases, of mountain men. Among these elite were Major Andrew Henry, Jedediah Smith, Etienne Provost and Daniel Potts. A young Jim Bridge, who had a previous westward voyage to his credit, was present. James Clyman, William Sublette, Louis Vasquez, Thomas Eddie and the mulatto Edward Rose also tossed in with Ashley’s group.
Ashley’s original plan had been to reach the beaver-rich land west of the Rockies. This was the valley of the Spanish River, or Rio Colorado which is now known as the Rio Verde or Green River in the western part of present-day Wyoming. But due to extreme problems with various Indian tribes Ashley was forced to change his plan of reaching this area via the Missouri, Yellowstone and Bighorn Rivers.
You might say that Ashley had to scrap, for sake of scalp, plan A. Plan B, perhaps for bountiful beaver, was put into action. Plan B was to send a party of men overland, directly west to Crow Country across the continental divide to the Spanish River.
One advantage to this new plan was in the person of Edward Rose who had previously made this trip and who had, also, lived with the Crow. Rose had accomplished this feat while employed by Manuel Lisa in 1807. It was the same adventure that had included mountain man and hunter Caleb Greenwood.
In the past, others had traveled this westward region. Further northward than Ashley’s overland party would travel the Wilson Price Hunt party had made the crossing. Somewhat southward Robert Stuart had done the same, only in an eastward direction.
Besides finding the best beaver country Ashley wanted his men to locate an easy pass, if there was one, over the Continental Divide. To do this, Ashley chose from eleven to about sixteen or seventeen men, depending on who is doing the telling. But more importantly, the party captained by Jedediah Smith, contained among its ranks Thomas Fitzpatrick as second in command, William Sublette, James Clyman, Thomas Eddie and Edward Rose. Two others by the names of Stone and Branch were included but the names of the others are lost.
