A crowd of about 800 pro-slavery Americans ransacked the town of Lawrence, Kansas.

The sacking of Lawrence occurred on May 21, 1856, when pro-slavery settlers, led by Douglas County Sheriff Samuel J. Jones, attacked and ransacked Lawrence, Kansas, a town that had been founded by anti-slavery settlers from Massachusetts who were hoping to make Kansas a free state. The incident fueled the irregular conflict in Kansas Territory that later became known as Bleeding Kansas.

Lawrence is a city in and the county seat of Douglas County, Kansas, United States, and the sixth-largest city in the state. It is in the northeastern sector of the state, astride Interstate 70, between the Kansas and Wakarusa Rivers. As of the 2020 census, the population of the city was 94,934. The city is a college town with a significant student population, because it is home to both the University of Kansas (KU) and Haskell Indian Nations University (HINU).