Persephone, population approximately 260,000, is humanity's first colony outside of their solar system, established in 2738 by the residents of the vast colony ships Christopher Columbus, Marco Polo, and Yuri Gagarin. Located below the twenty-eighth parallel in Persephone's relatively seismically stable zone, the colony originally existed of the three ships after a deliberate controlled collision into the terrain to serve as primitive homes while more thorough habitations were imported from Earth and constructed on-site. Though these three ships remain the centre, a series of prefabricated buildings brought in from Earth now make up the large majority of the colony, linked together by a series of tubes.

Persephone's main industry is logging: the native wood of the planet is prized on Earth and in finer rooms around the galaxy for its strength and beauty, and it is sufficiently common on the planet that it can be found holding together even the meanest hovel. Agriculture succeeds at a level allowing the colony to subsist on its own, and most of the other jobs are directly related to Persephone's status as humanity's centre of galactic trade, as the only planet under humanity's control where aliens are permitted to set foot. Though the colony has been comprehensively mapped by satellite, outside the immediate area of the colony the planet is almost entirely uninhabited, as the atmosphere is rich in sulfites and nitrates, leading to a choking death for any human caught outside without protection.