Theodotus of Chios[1] (Greek: Θεόδοτος) (died in 43 or 42 BC) was the rhetoric tutor of the young Egyptian king Ptolemy XIII.
Ptolemy XIII and his advisers were forced to move with their army into position near the Egyptian border fortress Pelusium, not far from the troops of Cleopatra.
At that time, end of July 48 BC, the Roman triumvir Pompey – who had lost the Battle of Pharsalus against Julius Caesar – appeared at the Egyptian coast near Pelusium and asked the allied Pharaoh for asylum and assistance.
Caesar in his Commentarii de Bello Civili and the Roman poet Lucan in his Pharsalia do not mention the participation of Theodotus in this council, but other sources say his suggestion to murder Pompey was accepted.
He also demanded the payment of a large sum of money that the Ptolemaic government allegedly owed him for the military restoration of Ptolemy XII in 55 BC.