Yankee general. The high points of his career:
It took him 5 years to get through a 4 year course at West Point.
He brutalized the civilians in the Shenandoah Valley
After the war, he brutalized the people of Lousiana and Texas as head of the occupation government. His reputation as a tyrant finally got him removed from that post.
His most famous statement - "The only good Indian is a dead one."
He liked to attack the Indian camps in Winter, when distruction of food supplies would cause starvation. Another quote: "If a village is attacked and women and children killed, the responsibility is not with the soldiers but with the people whose crimes necessitated the attack."
Sympathetic bio here: http://www.pbs.org/weta/thewest/people/s_z/sheridan.htm