It is part of the ancient method of organization developed by the nomads of Central Asia based on the decimal system.[1] Tumen, which included 10,000 households and soldiers,[2] was the largest group and it was divided into ten mingghan.[1] A mingghan was made up of 10 jaghuns[2] or 100 arbans.[3] An account cited that once he becomes a guard, it is the duty of a mingghan commander's son to bring a younger brother and 10 other men to serve with him.[4]