Northern Africa 367: Austoriani
The 360s saw increasing raids on Roman Africa by desert tribes, in particular the Austoriani. Mired in corruption, the local government refused to provide military support to the attacked cities and even went so far as to persuade the emperor that reports of the raids were false.
26 Jun 363 Battle of Samarra▲
On 26 June 363 the Persians attacked the rearguard of the Roman army while it was marching near Samarra. Julian—who had been reconnoitering ahead unarmored—hurried back to stabilize the rear, but as he did so the Persians also attacked the vanguard and, at some point in the battle, the emperor was stabbed in the side with a cavalry spear. Although the Romans, despite suffering heavy losses, eventually repulsed their opponents, Julian died from his wound late that night.
11 Jul 363 Treaty of Dura▲
By early July 363 the Persians had largely trapped the invading Roman army around the city of Dura (Ad-Dawr) on the Tigris and were harassing them constantly. To escape this predicament, the newly-appointed Roman emperor Jovian accepted Shah Shapur II’s terms of peace, agreeing to cede a number of territories in Mesopotamia to Persia and to abandon the Roman alliance with Armenia in return for a thirty-year truce. The Roman cessions included the great fortress city of Nisibis, which Jovian personally handed over to the Persians as he and the remnants of his army withdrew to Syria.
364? First Austoriani Raid▲
During the reign of Jovian (363–4), in retaliation for the execution of one of their number for crimes committed in Roman Africa, the Austoriani ended a period of peaceful co-existence with the Romans and invaded the province of Tripolis. After raiding the fertile region around Leptis Magna and killing many peasants, they returned south with large quantities of booty and the local magistrate. Alarmed by this event, the people of Leptis called on Count Romanus, the commanding general for Africa, but the corrupt count refused to act unless provided with vast quantities of provisions and camels.
364 Valentinian–Valens Biarchy▲
After the end of winter 363–4, Valentinian and Valens traveled to Sirmium, where they divided command over the Roman Empire between them. By this agreement, Valentinian, as the senior Augustus, would preside over the prefectures of Gaul, Italy, and a (briefly) restored Illyricum, while Valens would preside over the East. The two emperors then took up their posts—in Mediolanum for Valentinian and in Constantinople for Valens—in time to assume their consulships at the beginning of 365.
367 Second Austoriani Raid▲
After facing no Roman reprisals for their first raid (c. 364), the Austoriani mounted a second major raid on Roman Africa in 367. Overrunning the territory around the cities of Leptis Magna and Oea (Tripoli), they killed a number of decurions before withdrawing with vast quantities of booty. Learning of this latest raid while in Gaul, an outraged Valentinian sent the tribune Palladius to Africa to inspect the defenses of Africa and investigate allegations of corruption against the commanding general, Count Romanus.