The goal of John Brown's raid on Harpers Ferry was to start a slave revolt within the United States. John Brown was a staunch abolitionist who wanted to get rid of the institution of slavery within the US. He felt that the only way to get rid of slavery was through violence. This is why he led a group of abolitionist and former slaves into the federal arsenal, so that they could take over enough weapons to create a nation wide slave revolt that would end the practice of slavery in the US.