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The Hasari were a race of people or political organization that ruled over a "nation". This "nation" was seized by the Cylons, an event which prompted the Colonies to liberate the Hasari "nation" and marked the beginning of the Thousand-Yahren War (TOS: "Saga of a Star World").
They are depicted in the 2003 Battlestar Galactica video game as whale-type creatures. A young William Adama comes across a transmission from a Hasari after encountering a destroyed Hasari craft.
- It is unclear what relationship the Colonies and Hasari shared, or even if the Hasari were still in existence at the time of the Battle of Cimtar.