The early cattle industry in Montana began to supply fur trading posts and missions with meat. In the 1850s, fur traders like Richard Grant began buying exhausted cattle from wagon trains traveling the Oregon Trail. These cattle were moved to range ground and "fattened up" before being herded back to the Oregon trail to be traded or sold.
When gold was discovered in the late nineteenth century, the cattle industry boomed. As more and more gold miners and prospectors poured into Montana, more and more food was needed to feed them. These new hunters quickly depleted Montana's wild game populations and then turned to ranchers for their meat supply.
With a new market for their cattle, ranchers liked Montana for its abundant open land for grazing as well as its high quality grass. The hardy Montana grasses dried standing up and strong winter winds blew snow away so the grass did not flatten, making it edible all winter. As hunters seeking furs decimated the bison herds, open-range ranching grew. The wide tracts of land claimed by the US Government in treaties and by force from Indian tribes made prime grazing country that was newly available to use.