Valentinian I

After the sudden death of Jovian, the Roman army elected Valentinian I as emperor at Nicaea. Valentinian was a capable military officer from Pannonia. He immediately appointed his brother Valens as co-emperor for the East, dividing the empire.

Valentinian I launched a series of campaigns against the Alamanni tribes who had invaded Gaul. He crossed the Rhine River and defeated them at the Battle of Solicinium (modern Rottenburg am Neckar). These campaigns secured the Rhine frontier for a decade.

Valentinian I ordered an extensive program of fortification along the Rhine and Danube borders. He built new forts, repaired existing walls, and established a system of watchtowers. This defensive strategy strengthened Roman control and deterred barbarian raids.

While receiving a delegation of Quadi barbarians at Brigetio on the Danube, Valentinian I became enraged at their insolent demeanor. He suffered a stroke (apoplexy) and died shortly after. His sudden death left the Western Empire in the hands of his young sons Gratian and Valentinian II.