The first action in Kansas was not between the rival armies. It was a guerrilla raid in August 1863 by pro-slavery irregular forces led by W.C. Quantrill. They attacked the city of Lawrence, a centre of anti-slavery sentiment. They killed about 180 men and boys and destroyed a number of buildings. As the raiders could be heard shouting “Remember Osceola!”, the attack was taken to be a reprisal for an earlier raid by anti-slavery jayhawkers on Osceola, Missouri. Some believed that it was also a response to the recent deaths of some of the raiders’ imprisoned womenfolk, when their jailhouse collapsed, perhaps by design. (Recent research shows that the collapse was almost certainly accidental.) The massacre outraged the Confederate government, which had granted recognition to Quantrill under the Partisan Ranger Act, but now withdrew support from irregular forces.