Arsinoe III Philopator
Arsinoe III Philopator (Greek: Ἀρσινόη Φιλοπάτωρ) was a queen consort and sister of King Ptolemaios IV Philopator of Egypt and the mother of King Ptolemaios V Epiphanes of Egypt. She and her husband were children of Ptolemaios III Euergetes and Berenike II.
Battle of Raphis
During the Fourth Syrian War against King Antiochos III Megas of Syria, Arsinoe accompanied Ptolemaios IV and his army on their march to a region near Raphia. A battle occurred there. When the battle seems to be going in Antiochos III's favor, Arsinoe encouraged the soldiers to defend themselves and their children and promised two minas of gold to each soldier if they obtain victory against their foes. The Egyptians then turned the tide of the battle and defeated Antiochos III.
When a bitter fight resulted, and matters were turning out rather in favor of Antiochus, Arsinoë went to the troops with wailing and tears, her locks all disheveled, and exhorted them to defend themselves and their children and wives bravely, promising to give them each two minas of gold if they won the battle. And so it came about that the enemy was routed in the action, and many captives also were taken.— 3 Maccabees 1:4–1:5 (NRSV)
Her husband Ptolemaios IV possessed a mistress named Agathokleia, and Agathokleia's brother Agathokles became a minister for Ptolemaios. Agathokleia and Agathokles wielded much influence over Ptolemaios IV.
When Ptolemaios IV died, Agathokleia, Agathokles, and another influential minister named Sosibius had Philammon assassinate Arsinoe III Philopator so that Agathokles and Sosibius could serve as regents for Arsinoe's young son Ptolemais V Epiphanes. Agathokles later had Sosibius killed as well.
The people learned of the truth behind Arsinoe's death. Agathokles (the younger) was killed, and a mob killed and dismembered Agathokleia, their sisters, and their mother Oinanthe. A mob also killed Philammon.
Tlepolemos then became Ptolemaios V's regent.