Ptolemy III Euergetes I, (Ptolemaeus III) (Evergetes, Euergetes) (246 BC-222 BC). The third ruler of the Ptolemaic dynasty of Egypt, he was the eldest son of Ptolemy II of Egypt Philadelphus and Arsinoe II of Egypt. He came to power in 246 BC upon the death of his father. He is most noted for his invasions of the northern kingdom of Syria which he commenced upon the murder of his eldest sister and wife Berenice II of Egypt.
He was the father of Arsinoe III of Egypt.
See also: Eratosthenes