Europe 363: Treaty of Dura
Julian’s Persian Campaign came to an abrupt end in June 363, when the emperor himself was killed in battle. Withdrawing north along the Tigris with the battered remnants of the Roman invasion force, the new emperor Jovian agreed to cede Roman Mesopotamia to Persia and to end the Roman alliance with Armenia in return for peace.
22 Jun 363 Battle of Maranga▲
Concluding that Ctesiphon was too strong to be taken, Julian decided to cross the Tigris and march inland with his army. As it would be too difficult to transport his fleet along this route, he had the ships burned to avoid them falling into Persian hands. After weakening the Romans by setting fire to crops and grasslands on their route, the Persians attacked them with a large force near Maranga in June 363 but were driven off in a hard-fought battle.
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.
27 Jun 363–17 Feb 364 Reign of Jovian▲
In June 363, the day after the death of Julian, Jovian, chief officer of the imperial bodyguard, was elected emperor by the troops in Persia. Jovian quickly made peace with the Persians by ceding territory in the East to them, then began his march west to take up his position in Constantinople. En route, he restored Christianity to its former role in the Roman Empire, but his short reign came to an abrupt end when he died suddenly—possibly from poisonous paint fumes—at Dadastana, between Ancyra and Nicaea, at the age of just 33.
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.