Atossa (Ancient Greek: Ἄτοσσα, from Old Persian *Utauθa, New Persian:آتوسا Atosa, in Avestan: Hutaosā) was an Achaemenid empress and daughter of Cyrus the Great and Cassandane. She lived from 550 BC to 475 BC and probably was a sister of the Persian king Cambyses II.
Atossa married Darius I during 522 BC after he, with the help of the nobleman Otanes, defeated the followers of a man claiming to be Bardiya (Smerdis), the younger brother of Cambyses II.
Herodotus records in The Histories that Atossa was troubled by a bleeding lump in her breast. She wrapped herself in sheets and sought a self-imposed quarantine. Ultimately, a Greek slave, Democedes, persuaded her to allow him to excise the tumor.
Xerxes I was the eldest son of Atossa and Darius. Atossa lived to see Xerxes invade Greece. Being a direct descendent of Cyrus the Great, Atossa had a great authority within Achamenian imperial House and court. Atossa's special position enabled Xerxes, who was not the eldest son of Darius, to succeed his father.
Atossa Genetics was named after Queen Atossa by its founder, Dr. Steven Quay, in 2009. The NASDAQ public company is dedicated to helping women with breast cancer through its development of pharmaceuticals to treat early stage tumors. The company's logo is a rendition of a bust of Atossa held in the National Museum of Iran.