Donner Party, group of emigrants to California who in the winter of 1846–47 met with one of the most famous tragedies in Western history. The California-bound families were mostly from Illinois and Iowa, and most prominent among them were the two Donner families and the Reed family. In going West they took a little-used, supposedly shorter route after leaving Fort Bridger; the route proved arduous and and they were delayed. They suffered severely in crossing the salt flats W of Great Salt Lake, and dissensions and ill feelings in the party arose when they reached what is today Donner Lake in the Sierra Nevada. They paused (Oct., 1846) to recover their strength, and early snow caught them, falling deep in the passes and trapping them. Their limited food gave out, the cold continued, and the suffering of the group, some two thirds of them camped on Alder Creek and the remaining 22, including all of the Donner family, camped at Donner Lake, grew intense.
A party of 15 snowshoers that attempted to make its way through the snow-choked passes in December to get help suffered horribly; about half of them survived to get aid from Sutter's Fort. Many of the emigrants died during the winter. Some surviving members of the Donner Party were reputedly driven to cannibalism, but despite archaeological examinations of the remains, cannibalism has never been definitively proved. Finally, expeditions from the Sacramento valley made their way through the snowdrifts to rescue the hunger-maddened migrants. Only about half of the original party of 81 reached California. The survivors later disagreed violently as to the details of (and particularly the blame for) the disaster. Donner Lake, named for the party, is today a popular mountain resort near Truckee. The large bronze Pioneer Monument (1918) erected at the lake is dedicated to the party. Nearby Donner Pass has a U.S. weather observatory.
See C. F. McGlashan, History of the Donner Party (1879, repr. 1966); G. R. Stewart, Ordeal by Hunger (1936, new ed. 1960); E. Rarick, Desperate Passage (2008).