From Halopedia, the Halo wiki
Gilgamesh is a human colony world. It is a lawless world, mainly controlled by mobsters and Insurrectionists, and is relatively obscure as a result. The planet has a large and refined brothel on its surface.
In 2552, the AI construct Cortana wired a transfer of funds to the Gilgamesh brothel, masquerading as Colonel James Ackerson. This was her form of payback for his heavy-handed attempt to make sure that Dr. Halsey's MJOLNIR AI-Spartan integration test failed. Since the brothel would send a confirmation of this action, she knew that this action would make his wife quite mad and in turn disrupt his life.
Gilgamesh was a Sumerian king that ruled Mesopotamia (specifically Assyria) circa 2650 BC. He was the Sumerian equivalent to Hercules, as he was considered a demigod of superhuman strength.
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