Abstract
In 1855, a small group of predominately Mexican men murdered five white people and one Native American man in the now non-existent mining town of Lower Rancheria in Amador County, California. In the wake of the Rancheria massacre, the Anglo-American residents in the surrounding region retaliated violently against the Spanish-speaking community. White lynch mobs hanged as many as thirty innocent Mexican men and forced the rest of the large Mexican and Chilean population to leave the area. Using primary source materials, including personal correspondence, journal entries, and newspaper accounts, this thesis explores the racial, economic, and political environment within which such a violent episode was able to occur. It also seeks to provide an understanding of the historical context for Anglo-American prejudice against Mexicans, as well as a psychological explanation for the onset of mob violence.