Brown began his major abolitionist activities in Kansas. While there, he was responsible for the murders of at least five men and committed many violent crimes in an attempt to keep Kansas for the free soilers. The five men they murdered were all pro slavery and thought to be among those who had burnt a Kansas town. The issue of John Brown's insanity actually was a topic of debate during his trial. His lawyer brought forth a telegram giving reason to doubt Brown's sanity.
Insanity is hereditary in that family.
His mother's sister died with it, and a daughter of that sister has been two years in a lunatic asylum. A son and daughter of his mother's brother have also been confined in the lunatic asylum, and another son of that brother is now insane and under close restraint. I look upon it as a miserable artifice and pretext by those who oughtt to take a different course in regard to me, if they toook any at all, and I view it with more contempt then otherwise. As I remarked to Mr. Green, insane persons, so far as my experience goes, have but little ability to judge of their own sanity, and, if I am insane, of course I should think I know more then the rest of the world. But I do not think so.