Eighty-seven pioneers led by George Donner set out from Illinois for California on April 16, 1846. The expedition suffered a series of unfortunate events and circumstances, leading to the deaths of nearly half the party. Some resorted to cannibalism for survival. Rescuers arrived in February 1847, but only forty-eight members of the party survived.
James W. Marshall, a 36-year-old carpenter and handyman, discovered gold at a sawmill near Sacramento, California. The discovery set off the California gold rush. In 1849, 80,000 men arrived in California hoping to make a fortune in mining. Few struck it rich, and the gold rush lasted less than a decade.
In the Rush-Bagot Agreement, the United States and Britain agreed to substantially demilitarize the Great Lakes boundary between the US and British Canada, with each cutting their fleets to far fewer vessels. This was the first disarmament agreement made by the United States.