From ROI Wiki

Impdo is the president and leader of a Buyyor Worldship, known within his people as "Colony Four", that is initially located near the planet of Sebius, but later moves across the galaxy to another location after the fall of the UGW. During his time at Sebius, during the reign of the UGW, his colony serves as the home for the Buyyor ambassador to the UGW. When the ASW is formed, the ambassador moved to a different colony that was closer to the home planet of the new fledgling Alliance, relegating Impdo and Colony Four to the status of just a normal colony again.