Page "Constantius II" Paragraph 11

After, Constantius hurried east to Antioch to resume the war with Persia.

While Constantius was away from the eastern frontier in early 337, Shapur assembled a large army, including war elephants, and launched an attack on Roman territory, laying waste to Mesopotamia and putting Nisibis under siege.

Despite initial success, Shapur lifted his siege after his army missed an opportunity to exploit a collapsed wall.

When Constantius learned of Shapur's withdrawal from Roman territory, he prepared his army for a counter-attack, drilling them and upgrading the equipment of his cataphracts.

He spent most of his time defending the eastern border against invasions by the aggressive Sassanid Empire under king Shapur II.

These conflicts were mainly limited to Sassanid sieges of the major fortresses of Roman Mesopotamia, including Nisibis ( Nusaybin ), Singara, and Amida ( Diyarbakir ).

Although Shapur seems to have been victorious in most of the confrontations, the Sassanids were able to achieve little.

However, the Romans won a decisive victory at the Battle of Narasara, killing Shapur's brother, Narses.

Ultimately, Constantius was able to push back the invasion, Shapur failing to make any significant gains.

Meanwhile, his brother Constantine desired to retain control of Constans ' realm – leading Constantius ' two brothers into open conflict.

Constantine was killed in 340 near Aquileia during an ambush.

As a result, Constans took control of his deceased brother ’ s realms and became sole ruler of the Western two-thirds of the empire.

This division lasted until 350, when Constans was assassinated by forces loyal to the usurper Magnentius.