[Coin of Ptolemy II with Arsinoë II on the obverse, 3rd century BCE, Egypt]
[Source: Wikimedia Commons]
She was the daughter of Ptolemy I Soter and Berenike I.* Her father, formerly one of Alexander the Great’s generals, had taken control of Egypt after his friend and leader’s death. The exact date of her birth is unknown, with 316 being the accepted guess.
When Lysimachos died in battle in 281, Arsinoë took control of the city of Cassandreia and stayed there until she married her half-brother Ptolemy Keraunos a year later. Both of them claimed the Macedonian throne, so the hope was that a match between them would protect each from the other’s claim and instead strengthen both of their positions in a time when Alexander’s successors were all at war with each other. The marriage ended Keraunos accused his wife of treason, killed her two younger sons, attempted to kill the eldest and cast Arsinoë out. Justin, who is basically our only source on this, gives no clear explanation for why.
[Arsinoë II depicted as Isis, relief in the Philae temple of Isis, 3rd century BCE, Egypt]
[Source: Wikimedia Commons]
*Ptolemy was Berenike’s 2nd husband, while she in turn was his 4th wife. Arsinoë II and Ptolemy II had a lot of half-siblings.
**Whether or not they had any daughters is unrecorded. As usual.
***Pausanias says that some of his sources claim it was because Arsinoë fell in love with him and he spurned her advances. Given how standard this accusation is, it can probably be discarded in favor of the political explanation. If, that is, we accept that she had a hand in it, which is very possible but not a given.
Pausanias, Description of Greece, 1.6.8, 1.7.1 - Perseus
Marcus Junius Justinianus, Epitome of the Philippic History of Pompeius Trogus, 17.2, 24.2-3 - Forum Romanum
Donnelly Carney, Elizabeth. Arsinoë of Egypt and Macedon. New York: Oxford University Press, 2013.
Arsinoe II - Wikipedia
Arsinoe II - Egyptian Royal Genealogy