Abolitionist john brown was responsible for leading what violent incident in kansas?

John Brown was responsible for being one of the leaders for "Bleeding Kansas", as well as leading a raid on Harpers Ferry.

Before the raid on Harpers Ferry, Brown and his sons as well as some followers entered into Kansas and attacked and murdered some well-known pro-slavery citizens that lived in the area. After that, he went around to gather up support for the abolitionist cause, and decided to restock military supplies at Harpers Ferry. However, this was quickly found out by the US army, who sent soldiers under Lee (who was then still a US general), which quickly surrounded and captured Brown.

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