Valentiniānus in Harpers Dictionary of Classical Antiquities

A Roman emperor (A.D. 364- 375), was the son of Gratianus, and was born A.D. 321, at Cibalis in Pannonia. His first wife was Valeria Severa, by whom he became the father of the emperor Gratianus. He held important military commands under Julian and Jovian; and on the death of the latter, in February, 364, Valentinian was elected emperor by the troops at Nicaea. A few weeks after his elevation Valentinian, by the desire of the soldiers, associated in the empire his brother Valens, and assigned to him the East, while he himself undertook the government of the West. Valentinian was a Catholic, though his brother Valens was an Arian; but he did not persecute either Arians or heathens. He possessed good abilities, prudence, and vigour of character. He had a capacity for military matters, and was a vigilant, impartial, and laborious administrator. The greater part of Valentinian's reign was occupied by the wars against the Alemanni and the other barbarians on the Roman frontier, in which his operations were attended with success. He not only drove the Alemanni out of Gaul, but on more than one occasion crossed the Rhine, and carried the war into the enemy's country. His usual residence was Treviri (Trèves). In 375 he went to Carnuntum on the Danube, in order to repel the Quadi and Sarmatians, who had invaded Pannonia. After an indecisive campaign he took up his winter-quarters at Bregetio. In this place, while giving an audience to the deputies of the Quadi, and speaking with great heat, he fell down in a fit and expired suddenly, on the 17th of November (Amm. Marc. xxviii.-xxx.; Zosim. iv. 17).