Hive Worlds are comparatively scarce across the Imperium as a whole, and are even more uncommon in the fringes of Imperial space like the Koronus Expanse. A confluence of multiple factors facilitating human colonization has allowed the population of Gallbreath to grow to some thirty billion souls, however, and the name of the planet and that of the solar system are now nearly synonymous after four centuries of habitation.
Unusually, power is split with little open contention between 8 autonomous city-states, each contributing to the Imperial tithes through speciality manufacturing and each built on the banks and foothills of vast geothermal vents. Much of the surface is otherwise treacherous fields of splintering ice, whirling storms, and rugged and crumbling mountains.