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Anderson subsequently returned to Missouri as the leader of his own group of raiders and became the most feared guerrilla in the state, robbing and killing a large number of Union soldiers and civilian sympathizers. Anderson, perhaps falsely, implicated Quantrill in a murder, leading to the latter's arrest by Confederate authorities. In late 1863, while Quantrill's Raiders spent the winter in Sherman, Texas, animosity developed between Anderson and Quantrill. He took a leading role in the Lawrence Massacre and later took part in the Battle of Baxter Springs, both in 1863. After a building collapse in the makeshift jail in Kansas City, Missouri left one of them dead in custody and the other permanently maimed, Anderson devoted himself to revenge. Anderson's bushwhacking marked him as a dangerous man and eventually led the Union to imprison his sisters. He became a skilled bushwhacker, earning the trust of the group's leaders, William Quantrill and George M.
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In early 1863 he joined Quantrill's Raiders, a group of Confederate guerrillas which operated along the Kansas–Missouri border. There he robbed travelers and killed several Union soldiers. After a Union loyalist judge killed his father, Anderson killed the judge and fled to Missouri. Raised by a family of Southerners in Kansas, Anderson began to support himself by stealing and selling horses in 1862. Anderson led a band of volunteer partisan raiders who targeted Union loyalists and federal soldiers in the states of Missouri and Kansas.
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1840 – October 26, 1864), known by the nickname "Bloody Bill" Anderson, was an American soldier who was one of the deadliest and most notorious Confederate guerrilla leaders in the American Civil War.
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