Artemisia I (flourished 5th century bce) was the queen of Halicarnassus, a Greco-Carian city in the ancient district of Caria (in southwestern Anatolia), and of the nearby islands of Cos, Calymnos, and Nisyrus about 480 bce.
Artemisia ruled during the overlordship of the Persian king Xerxes (reigned 486–465) and participated in Xerxes’ invasion of Greece (480–479). Despite her able command of five ships in the major naval battle with the Greeks off the island of Salamis near Athens, the Persian fleet suffered a severe defeat. Herodotus, a historian who is believed to have been born in Halicarnassus about 484 bce, claimed that Xerxes acted on her advice when he retreated from Greece at once rather than risk another engagement.