In Sumerian and Akkadian (Babylonian and Assyrian) mythology, the Gallus (also called gallu demons or gallas [Akkadian: gallû]) were great demons/devils of the underworld.
Gallu demons hauled unfortunate victims off to the underworld. They were one of seven devils (or "the offspring of hell") of Babylonian theology that could be appeased by the sacrifice of a lamb at their altars.
Inanna (or Ishtar) was freed by gallu demons sent by Enki while she was on a journey to the underworld. An especially fierce gallu demon, the monstrous Asag, was slain by Ninurta using the enchanted mace Sharur.
The word gallu may also refer to a human adversary, one that is dangerous and implacable.