Short answers, pulled from the story.
William Quantrill led Quantrill's Raiders, the best known pro-Confederate partisan guerrilla band of the Civil War. His men included Jesse and Frank James, who later formed their own outlaw gang and continued robberies for years.
In August 1863, Quantrill led his Raiders in an attack on Lawrence, Kansas that killed more than 180 civilians and burned a quarter of the town's buildings. Abolitionist U.S. Senator Jim Lane, one of the main targets, escaped by fleeing into corn fields.
Quantrill was granted a field commission as a captain in the Confederate army on the 15th of August 1862, under the Partisan Ranger Act. The Confederate government later withdrew its support after the Lawrence massacre.
After the raid, Quantrill led his men south to Texas, where they wintered in 1863-1864 while continuing to raid along the way. Their retreat included the Battle of Baxter Springs, where they killed near 100 Union troops.
The Confederate government was outraged by the brutality of the Lawrence massacre and withdrew even tacit support for the bushwhackers. By 1864, Quantrill had lost control of his men, and the group splintered into smaller bands.
Quantrill lost control of his men over the winter of 1863-1864, and the group split into bands led by figures such as 'Bloody Bill' Anderson and George M. Todd. Quantrill himself was later cornered in Kentucky and reportedly died from his wounds within a week, while the last surviving member of the Raiders lived until 1940.