Hirtius, Aulus (c. 90–43 BC)

Roman soldier and historian. He was a friend of the orator Cicero and of Julius Caesar, under whom he served in Gaul. He completed Caesar's De Bello Gallico/The Gallic War by adding the eighth book. As consul 43 BC he sided with Octavian (the future emperor Augustus) during the Mutina campaign against Mark Antony and was killed in action.

The narrative of Caesar's Egyptian campaign, the Bellum Alexandrinum, is possibly the work of Hirtius.