the son of Cleopatra, originally called Ptolemaeus as an Egyptian prince, was born soon after the departure of Julius Caesar from Alexandria in B. C. 47, and probably accompanied his mother to Rome in the following year. Cleopatra said that he was the son of Julius Caesar, and there seems little doubt of this from the time at which Caesarion was born, from the favourable reception of his mother at Rome, and from the dictator allowing him to be called after his own name. Antonius declared in the senate, doubtless after Caesar's death and for the purpose of annoying Augustus, that the dictator had acknowledged Caesarion as his son; but Oppius wrote a treatise to prove the contrary.

In consequence of the assistance which Cleopatra had afforded Dolabella, she obtained from the triumvirs in B. C. 42 permission for her son Caesarion to receive the title of king of Egypt. In B. C. 34, Antony conferred upon him the title of king of kings; he subsequently called him in his will the son of Caesar, and after the battle of Actium (B. C. 31) declared him and his own son Antyllus to be of age. When everything was lost, Cleopatra sent Caesarion with great treasures by way of Aethiopia to India; but his tutor Rhodon persuaded him to return, alleging that Augustus had determined to give him the kingdom of Egypt. After the death of his mother, he was executed by order of Augustus. (D. C. 47.31, 49.41, 1. 1, 3, 51.6 ; Suet. Jul. 52, Aug. 17; Plut. Cues. 49, Anton. 54, 81, 82.)