Semiramis was the legendary Lydian-Babylonian wife of Onnes and of Ninus, who succeeded the latter on the throne of Assyria, according to Movses Khorenatsi. Legends narrated by Diodorus Siculus, who drew primarily from the works of Ctesias of Cnidus, describe her and her relationships to Onnes and King Ninus.

Ninus, according to Greek historians writing in the Hellenistic period and later, was the founder of Nineveh, ancient capital of Assyria. The figure or figures with which he corresponds in Assyrian records is uncertain; an association or identification with Ninurta has been proposed. An identification with Shamshi-Adad I, Shamshi-Adad V, and/or a conflation of the two have also been suggested.