William T. Anderson (1839 – October 26, 1864), better known as Bloody Bill, was a pro-Confederate guerrilla leader in the American Civil War. Anderson led a band that targeted Union loyalists and Federal soldiers in Missouri and Kansas; he became notorious for the number of people he killed and the brutality of his behavior.
Raised by a family of Southerners in Kansas, Anderson began supporting himself by stealing and reselling horses in 1862. After his father was killed by a Union-loyalist judge, Anderson fled Kansas for Missouri. There, he robbed travelers and killed several Union soldiers. In early 1863, Anderson joined Quantrill's Raiders, a pro-Confederate group of guerrillas that operated in Missouri. He proved to be skilled at guerrilla warfare, earning the trust of the group's leaders, William Quantrill and George M. Todd. Anderson's acts as a guerrilla resulted in the imprisonment of his sisters; after one of them died in Union custody, Anderson devoted himself to revenge. He distinguished himself by taking a leading role in the Lawrence Massacre, and later participated in the Battle of Baxter Springs.
In late 1863, while Quantrill's Raiders spent the winter in Texas, animosity developed between Anderson and Quantrill. Anderson, perhaps falsely, implicated Quantrill in a murder, leading to the latter's arrest by Confederate authorities. Anderson subsequently returned to Missouri as the leader of a group of raiders and became the most feared guerrilla in the state, killing and robbing dozens of Union soldiers and civilian sympathizers throughout central Missouri. Although Union supporters viewed him as incorrigibly evil, Confederate sympathizers in Missouri saw his actions as justified, possibly owing to their mistreatment by Union forces. In September 1864, he led his guerrillas on a raid of Centralia, Missouri. Unexpectedly, they were able to capture a passenger train, the first time Confederate guerrillas had done so in the war. His men killed two dozen Union soldiers who had been passengers on the train, and later that day, set an ambush in which guerrillas killed more than one hundred Union militiamen. The day's events became known as the Centralia Massacre; in terms of number of lives lost and brutality shown to captives, it was possibly the most decisive guerrilla victory in the war. A month later, Anderson was killed in a battle against Union militia, to the joy of Union loyalists in Missouri. Historians have been mixed in their appraisals of Anderson: some see him as a sadistic, psychopathic killer, but others argue that the conditions in which he found himself are at least partly to blame for his actions.