Arsinoe IV was Cleopatra’s sister who was displayed in Julius Caesar’s Roman triumph in 46 BC. She was captured after taking part in the Alexandrian struggle against Caesar and Cleopatra.
Arsinoe was the youngest daughter of Ptolemy XII Auletes and claimed the Egyptian throne during the war of 48–47 BC. She escaped from Caesar’s custody in Alexandria, joined the Egyptian army, and was proclaimed queen. Her forces initially fought effectively, but the conflict ended with Caesar’s victory and the death of Ptolemy XIII.
Caesar brought Arsinoe to Rome as a prisoner and included her in his triumph of 46 BC. Triumphs traditionally displayed defeated rulers and commanders, but her appearance reportedly stirred public sympathy. Caesar therefore spared her life rather than having her executed after the ceremony.
Arsinoe was sent into exile at the Temple of Artemis in Ephesus. She remained a political threat to Cleopatra, who later supported her execution by Mark Antony in 41 BC. Arsinoe is often confused with Cleopatra’s other siblings, but she—not Berenice IV or Cleopatra V—was the sister paraded in Caesar’s triumph.