[3][4] Her ancestors were powerful—her paternal grandfather was Agathocles of Pella,[5] a nobleman contemporary to King Philip II of Macedon.
[6] Arsinoe I shared a name with her grandmother,[7] though it is unknown whether it was the mother of Lysimachus or of Nicaea as both women remain unnamed in ancient sources.
Between 289/88[8] and 281 BC,[9] Arsinoe I married her distant maternal cousin, Ptolemy II Philadelphus, pharaoh of the Ptolemaic Kingdom.
Following the death of Lysimachus, Arsinoe II had married her half-brother, Ptolemy Keraunos, but fled to Egypt following a dispute.
[13] The stele calls Arsinoe I the "king’s wife", but her name is not enclosed in the royal cartouche as was customary for an Egyptian queen.