Carolina Cavalry Regiment on August 22, 1862, Butler was elected its colonel. Participating in many major actions with Hampton's Legion and the 2nd SC Cavalry, Butler lost his right foot to rifle fire at Battle of Brandy Station. He attained the rank of brigadier general in February 1864 and was referred to as "General Butler" in the postwar period. Butler led a brigade in Wade Hampton's division of the Cavalry Corps. When Hampton took command of that corps, Butler became division commander. Late in the war, he transferred to the Carolinas together with Lt. Gen. Hampton, leading a division at the Battle of Bentonville. General Butler was wounded again in that action. Postbellum Financially ruined as a result of the war, Butler resumed his career as a lawyer in Edgefield. He was elected to the South Carolina House of Representatives beginning in 1866. He became a member of the Democratic Party and ran unsuccessfully for lieutenant governor in 1870 during the Reconstruction era. He was a member of the pro-black Union Reform party. In July 1876, Butler defended two white farmers in court in their complaint of being denied free passage on Main Street of Hamburg, South Carolina, when the local chapter of the black militia, part of the National Guard, was parading on Independence Day. In court, Butler demanded that militia members turn over their arms to him, which they refused. Hundreds of white paramilitary members came to town and attacked the armory, where the militia company had taken refuge. They killed two freedmen on the street, including the town marshal, and later murdered five freedmen they had taken prisoner. One white man had been killed in early gunfire (see Hamburg massacre). In 1877, after Federal troops had been withdrawn under a national Democratic compromise, Reconstruction ended. The Democratic Party regained control of the state in the 1876 elections. The South Carolina state legislature elected Butler to the United States Senate. During Senate hearings on his election, Butler was accused by Edgefield African-American leader Harrison N. Bouey of threatening to kill him and other local men. Butler served in the U.S. Senate for three terms, from 1877 to 1895, but lost for re-election in the South Carolina legislature to Benjamin Tillman, who was popular after serving as governor. In 1890 while serving in the Senate, Butler introduced a bill to provide federal aid to African Americans who would emigrate