Downieville is an unincorporated community in and the county seat of Sierra County, California, United States.

Downieville was settled in late 1849 during the California Gold Rush and was first known as "The Forks" for its geographical location and shortly thereafter was renamed after Major William Downie (1820-1893), a Scotsman who led the expedition up the North Fork of the Yuba River and who was the town's first mayor. Major Downie's travels are documented in his 1893 autobiography, "Hunting for Gold." Downieville reached a peak population of over 5,000 people in 1851 but declined sharply by 1865. Downieville is situated at the confluence of the Downie River and North Fork of the Yuba River. Downieville was vying to become the state capital of California along with fifteen other California communities in 1853 before the capital was moved to Benicia, and then shortly thereafter its current location in Sacramento. In July 1851 Downieville gained a distinction it may not have wanted when a mob lynched a Mexican woman, known as Juanita, for the murder of a white miner. It remains the only lynching of a female in California history. See more....