In 1203, Genghis Khan, in an effort to strengthen his army, ordered a reform that reorganised his army's structure while breaking down the traditional clan- and kindred-based divisions that had previously fragmented the society and military. He arranged his army into arbans (inter-ethnic groups of ten), and the members of an arban were commanded to be loyal to one another regardless of ethnic origin.[5] Ten arbans made a zuun, or a company; ten zuuns made a myangan, or a battalion; and ten myangans formed a tumen, or an army of 10,000.