Tivoli
Tivoli was the most conquered planet in the galaxy. It was inhabited by a species of rodent-like humanoids. They were one of the oldest civilisations in the galaxy and simply let invaders do as they wished. Their anthem was "Glory To <Insert Name Here>" and their cities were designed to be comfortable for the invading armies. It was green in color when seen from space. (TV: The God Complex) Its capital city had a sign saying "If you occupied us, you'd be home by now." (TV: Before the Flood)
During the 20th century, Tivoli was ruled by the Fisher King for ten years, before being liberated by the Arcateenians. The Arcateenians became so irritated by the Tivolians that they chose to enslave them as well. An undertaker, Albar Prentis, was sent by them to bury the Fisher King on a "barren, savage outpost" in accordance with Arcateenian custom. (TV: Before the Flood)
Gibbis was a native of Tivoli. (TV: The God Complex).