Babylon, a city of shifting identities, was a constant point of reference for the Mediterranean world. This article explores the portrayal of the Babylonian queen Semiramis in Greek and Roman sources, demonstrating how ancient Near Eastern identities were constructed from the external perspective of Mediterranean cultures. Herodotus first mentioned Semiramis in the fifth century bce, associating her with Babylon’s architectural wonders. Ctesias described her as an outstanding, but in many respects flawed military leader. In contrast, during the final stage of the Roman Republic, Diodorus Siculus reshaped Ctesias’ narrative and portrayed her more positively, emphasizing her beauty, virtues, courage, and intelligence. During the Roman Empire, Semiramis remained a remarkable figure who accomplished great deeds, but later authors introduced negative aspects to her story. The Augustan Age portrayed her negatively, with new elements added, such as sodomy and murder, and used her as a stand-in for Cleopatra. Both queens were denigrated as female rulers and foreigners, emphasizing cultural differences between Mesopotamian and Roman identities. The portrayal of Semiramis served to categorize and describe Mesopotamian culture, rather than to understand it. Ultimately, this article shows how Semiramis reflects different perceptions of Babylonia/Assyria and how her portrayal shifted over time in ancient literature, serving as part of Augustan propaganda to pass judgment on Cleopatra and emphasize cultural differences.