The Donner Party was led by George Donner along with his wife Tamsen Donner, in June 1846 Springfield, Illinois, they had set west towards California. They had intentionally followed the regular California Trails to Fort Bridger, Wyoming. From there they had decided to leave the trail and take a new and supposedly "shorter route".
There easier passage was through the Wasatch Mountains where later they had gotten stuck and had to spend the winter there. The pioneers were there for several days before they had sent a messenger to try and find a way out without any harm done to the wagons. The messenger had come back a few days later and told them to find a new route. The emigrants had to carve their own road. They had finally made it to the Wasatch Mountains and made it to the Great Salt Lake. That route had cost them 18 valuable days.
(What a very eventful picture i have here)
The "shortcut" to California had got the Donner Party cross Sierra Nevada Mountains late in season. On October 28, 1846 a heavy snow storm blocked the high mountains pass for them to get through making them stuck again but this time in a frozen wilderness. After 3 weeks of being stuck in the snow there food had ran out completely. They had reacted to eating tree bark and dead leaves, some even resorted to cannibalism.
They had been there for five months and had twenty wagons left. By the time they had gotten to California only 45 out of the 89 pioneers and emigrants had made it. how some dies are mysteries but others are from cannibalism, others from starvation and the majority from several illnesses that were passed around or from the plants.