The sanctuary planet (or planets) for defeated Houses Major and Minor, established under the terms of the Great Convention and maintained by the Spacing Guild. Its location was one of the most closely guarded secrets in the Imperium. Tupile also served as the Guild's original support base, where Ixian refugees led by Aurelius Venport first established the Society of Mystic Mariners and laid the groundwork for what would become the Spacing Guild and its monopoly on interstellar travel.