Trapped in the Mountains
On October 31st, when the party was still 150 miles from Sutter's Fort, a storm hit, dumping several feet of snow. They became trapped in the Sierra Nevada Mountains and were forced to build a winter camp with little food to sustain them. When the food ran out, some survived by eating the corpses of their companions. It was several weeks before rescue parties could be sent to help because of the Mexican War. Even after the war ended, not everyone could be rescued at once because of the harsh weather conditions and difficult terrain.
The last of the survivors reached Sutter's Fort (now Sacramento) almost exactly one year later. Of the 87 members of the Donner Party, 46 survived. While two-thirds of the men died, two-thirds of the women and children lived. Most of the Donner family itself died. For a while after, emigration to California slowed down, but when gold was discovered at Sutter's Creek in January 1848, gold-hungry travelers rushed out West again.