Atossa (c. 550-475 BCE) was the **Achaemenid Persian empress** — daughter of Cyrus the Great, sister and wife of Cambyses II, wife of Darius the Great, **mother of Xerxes I**. The most powerful woman of the Persian Empire at its height, she was Darius's chief political adviser. **The world's earliest documented case of breast cancer is recorded as occurring to Atossa**, treated by the Greek physician Democedes.
Featured in Aeschylus's The Persians.
Atossa reduces to two — the number of Persian empress.