Arsinoe II of Egypt

Arsinoë II (Ancient Greek: Ἀρσινόη, 316 BC – unknown date between July 270 and 260 BC) was a Ptolemaic Greek Princess of Ancient Egypt. Through marriage she became Queen of Thrace, Asia Minor and Macedonia as wife of King Lysimachus (Greek: Λυσίμαχος), and later co-ruler of Egypt with her brother-husband Ptolemy II Philadelphus (Greek: Πτολεμαῖος Φιλάδελφος, "Ptolemy the sibling-loving").

Arsinoë was the first daughter of Pharaoh Ptolemy I Soter (Greek: Πτολεμαίος Σωτήρ, "Ptolemy the Savior"), founder of the Hellenistic state of Egypt, and his second wife Berenice I of Egypt.

At about age 15, Arsinoë married King Lysimachus (who was then around 60 years old), to whom she bore three sons: Ptolemy I Epigone,Lysimachus and Philip. In order to position her sons for the throne, she had Lysimachus' first son, Agathocles, poisoned on account of treason. After Lysimachus' death in battle in 281 BC, she fled to Cassandreia (Greek: Κασσάνδρεια) and married her paternal half-brother Ptolemy Keraunos, one of the sons of Ptolemy I from his previous wife, Eurydice of Egypt. The marriage was for political reasons as they both claimed the throne of Macedonia and Thrace (by the time of his death Lysimachus was ruler of both regions, and his power extended to Southern Greece and Asia Minor). Their relationship was never good. As Ptolemy Keraunos was becoming more powerful, she decided it was time to stop him and conspired against him with her sons. This action caused Ptolemy Keraunus to kill two of her sons, Lysimachus and Philip, while the eldest, Ptolemy, was able to escape and to flee north, to the kingdom of the Dardanians. She herself went to Alexandria, Egypt to seek protection from her brother, Ptolemy II Philadelphus.

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