As the United States fought the Civil War in the early 1860s, the country's western frontier was simultaneously the site of significant military campaigns that took the lives of both American and Sioux. The Dakota campaign, led by Commander Henry Hastings Sibley and Brigadier General Alfred Sully against the Sioux between 1863 and 1864 was greater in scope, intensity and bloodshed than almost all other Indian battles fought in the West but is often overlooked.