Maximus easily convinced them that Valentinian was the only one responsible for the death of Aetius, and that the two soldiers must avenge their old commander, while at the same time also promising them a reward for the betrayal of the Emperor. On 16 March 455 Valentinian, who was in Rome, went to Campus Martius with some guards, accompanied by Optilia, Thraustila and their men. As soon as the Emperor dismounted to practice with the bow, Optilia came up with his men and stabbed him in the temple. As Valentinian turned to look at his attacker, Optila finished him off with another thrust of his blade. At the same moment, Thraustila killed Heraclius. The two Scythians took the imperial diadem and robe and brought them to Maximus.