HIRTIUS, Atreus, one of Caesar's chief supporters and most intimate friends. He was with him as legates in Gaul. After the civil war broke out in 49 B.C., he seems to have been generally stationed in Rome to protect Csar's interests there. He was a personal friend of Cicero, and used his influence with Caesar in behalf of the orator's brother and nephew. He was nominated along with Pansa by Caesar for the consulship of 43 sac.; and after the dictator's assassination in March 44, this honour made him for a short time one of the leading actors in that troubled time. The consuls supported the senatorial party against Antony, and led their armies into Umbria, where Antony was blockading Dec. Brutus in Mutina. On March 27th a double battle was fought : in the first Antony had the upper hand, and Pansa was mortally wounded; and in the second Hirtius completely defeated the enemy, but was himself killed in the subsequent assault on the enemy's camp. Hirtius was perhaps an author : the eighth book of Csar's commentaries on the Gallic war, which was certainly not written by Caesar himself, is commonly attributed to him; and the accounts of the Alexandrian, African, and Spanish wars are perhaps also due to his pen.