Amestris (Greek: Άμηστρις, Amēstris, perhaps the same as Άμαστρις, Amāstris, from Old Persian Amāstrī-, "strong woman") was the wife of Xerxes I of Persia, mother of Achaemenid King of Kings Artaxerxes I of Persia.
She was known to have been poorly regarded by ancient Greek historians.
Amestris was the daughter of Otanes, one of the seven nobleman who killed the magus impersonator of the Persian king Bardiya in 522 BC. After this, Darius I the Great of Persia started his reign. According to the ancient Greek historian Herodotus, Otanes was honoured with royal marriages. Darius I married Otanes' daughter Phaedymia while Otanes married a sister of Darius, who gave birth to Amestris.
When Darius died in 486 BC, Amestris was married to the crown prince, Xerxes. Herodotus describes Amestris as a cruel despot:
I am informed that Amestris, the wife of Xerxes, when she had grown old, made return for her own life to the god who is said to be beneath the earth by burying twice seven children of Persians who were men of renown.
Herodotus, Histories 7.114.
The origin of this story is unclear, since known records and accounts indicate that human sacrifices were not permitted within the Persian religion. Also since most accounts of the time are from Greek sources, and due to the involvement of Greece as an opponent of Persia, it is possible that not all accounts are accurate.
Amestris is a character in the opera Serse by George Frideric Handel (italianized as "Amastre"). In the opera, Amestris is about to marry Xerxes (Serse), yet he falls in love with another woman and wants to marry her instead. Amestris disguises herself as a man in order to be near him. At the end of the opera, Xerxes is sorry for the things he did and asks Amestris once more to be his wife.
Amestris also found its way into popular culture through the manga and anime Fullmetal Alchemist which is set in the country of Amestris. Fullmetal Alchemist also referenced Xerxes as the fallen city in the middle of the great desert between Amestris and Xing.