In June 1877, several bands of the Nez Perce, resisting relocation from their native lands in northeast Oregon to a reservation in North-Central Idaho, attempted to escape east through Idaho, Montana, and Wyoming over the Rocky Mountains into the Great Plains. By September, they had traveled nearly one thousand miles and fought several battles in which they defeated or held off the U.S. Army forces pursuing them. At Canyon Creek, the Nez Perce held off and escaped from a cavalry force that outnumbered them by at least two to one, but the loss of about 400 horses to Crow scouts increased the burden on their remaining, increasingly worn-out horses and slowed their flight toward Canada.