The Sye'lla Massive Spatial Army was created by the United Nations during the Interplanetary War of the mid-twenty-second century. After the S.M.S.A victory, overpopulation on Shadow Moon became a major issue in the early twenty-second century. The issue was resolved by colonizing and constructing vast cities on other planets in the Orion Arm of the galaxy, the Inner colonies and later, the Outer colonies.