Five of abolitionist John Brown's sons moved to Kansas in 1855. The unmarried sons, Owen, Salmon, and Frederick went first and were followed by John Jr. and Jason and their families later that spring. The Browns staked claims near Pottawatomie and were joined by their father and other family members in October. John Jr. became active in Free-State politics, served as a delegate to the Topeka Legislature, and was elected captain of the newly formed Pottawatomie Rifle Company. In May 1865 John Jr. and Jason set off with the Pottawatomie Rifles to defend Lawrence but were turned back. In the wake of the Pottawatomie Massacre, Jason and John Brown, Jr. were arrested and imprisoned. Frederick Brown was shot and killed shortly before the burning of Osawatomie in August 1865. The Browns left Kansas that fall.
From the description of John Brown family letters : Kansas, 1855-1856. (Unknown). WorldCat record id: 702137562
