Oliver P. Bayne, also known as O. P. Bayne, and sometimes mistakenly called Bain, was an active Free State man in southeast Kansas during the territorial period. When the civil war broke out he formed a Unionist independent cavalry company which operated on the Missouri-Kansas border in 1861. The company was disbanded--apparently on the order of the Federal authorities. A quick google of "Oliver P. Bayne" revealed a couple of sources that indicate he moved to the Nebraska territory in 1862.