Despite being one of the most erstwhile foes the U.S. government faced during the Indian Wars, the Sioux and their most famous leaders were grudgingly admired and eventually immortalized by the very people they fought. Sitting Bull and Crazy Horse remain household names due to their leadership of the Sioux at the fateful Battle of the Little Bighorn, where the native warriors wiped out much of George Custer's 7th Cavalry and inflicted the worst defeat of the Indian Wars upon the U.S. Army. Red Cloud remains a symbol of both defiance and conciliation, resisting the Americans during Red Cloud's War but also transitioning into a more peaceful life for decades on reservation.

However, one of the more overlooked conflicts the U.S. Army had with the Sioux took place during the American Civil War. It is known by various names, including the Dakota War, the US-Dakota War, the Dakota Uprising, the Sioux Outbreak, and Little Crow's War (after the principal Dakota leader), but the current most commonly used name for the war is the "Dakota War." Two of the four Dakota tribes in the state unleashed their anger and frustration on largely immigrant communities that were heavily German or Norwegian, and the massacres took a heavy toll. In the process, the conflict featured the largest Indian siege of an Army fort in American history, and the end of the conflict brought the largest mass execution in American history.

Indeed, the total loss of life during the Dakota War was perhaps the second largest of all the Indian Wars in North America, second only to the bloody King Philip's War in colonial New England in the late 17th century, during which more than 1,000 settlers were killed. Throughout the Dakota War, as many as 800 whites were killed, although no one knows the total, and many of the victims were buried in anonymous mass graves.