The temperate world of Aquinus was the second-most important world of the Aquinas system. It was ruled by the Council of Lords, a sort of senate elected among the nobility. The Lords retained their seat for a decade at a time. Aquinus was the military centre of the system, a significant part of the population working in the arms industry, or as members of the military. The planet held a population of around 150 million people, all of which were human. The population worked in all trades of life, though the most popular jobs were soldiers.