Berenice, c.273–21 B.C., queen of ancient Cyrene and Egypt She was the daughter and successor of King Magas of Cyrene. In 247 B.C. she married Ptolemy III, thereby effectively annexing Cyrene to Egypt. According to Callimachus and Catullus, he named a constellation after her, Berenice’s Hair (Coma Berenices). After her husband’s death she ruled jointly with their son, Ptolemy IV, until he had her put to death.

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