Initially of interest to the quarians due to a diverse biosphere featuring numerous edible plants compatible with their chirality, Has’Sey developed into a trading post thanks to its proximity to both Omega and several colony worlds of other species. As a new colony founded at the height of quarian power, Has’Sey featured a relatively small quarian population supported by hundreds of thousands of geth platforms, and when the Geth War broke out the quarians quickly found themselves outmatched. Their deaths seemed inevitable until the arrival of the defense force from the nearby batarian world of Eldraam, which rescued over 100,000 quarian civilians and subsequently bombarded the geth from space. In the aftermath of the destruction the Governor refrained from enslaving the evacuees, earning himself a place of honor in subsequent quarian folk history.
Batarian records of the incident record only that Governor Dasegar Alto assisted the quarians in subduing a slave uprising on Has’Sey using what was standard procedure in the Hegemony at the time. The nature of the geth led the batarians to err on the side of caution, and the bombardment of Has’Sey was so thorough as to obliterate any sign of the quarian colony and irreversibly damage the biosphere. In the hundreds of years since the Geth War, scouting and survey missions have reported the desertification of much of the planet, and no sign of geth activity has been detected.