Valentinian I (321 - November 17, 375) was a Roman emperor of the West (364 - 375). He was born at Cibalis, in Pannonia.
He had been an officer of the guard under Julian and Jovian, and had risen high in the imperial service. Of robust frame and distinguished appearance, he possessed great courage and military capacity. He was chosen emperor in his forty-third year by the officers of the army at Nicaea in Bithynia on February 28, 364, and shortly afterwards named his brother Valens colleague with him in the empire.
The two brothers, after passing through the chief cities of the neighbouring district, arranged the partition of the empire at Naissus (Nissa) in Upper Moesia. As emperor of the West, Valentinian took Italy, Illyricum, Spain, the Gauls, Britain and Africa, leaving to Valens the eastern half of the Balkan peninsula, Greece, Egypt, Syria and Asia Minor as far as Persia. They were immediately confronted by the revolt of Procopius, a relative of the deceased Julian. Valens managed to defeat his army at Thyatria in Lydia in 366, and Procopius was executed shortly afterwards.
During the short reign of Valentinian there were wars in Africa, in Germany and in Britain, and Rome came into collision with barbarian peoples of whom we now hear for the first time -- Burgundians, Saxons, Alamanni.
The emperor's chief work was guarding the frontiers and establishing military positions. Milan was at first his headquarters for settling the affairs of northern Italy; next year (365) he was at Paris, and then at Reims, to direct the operations of his generals against the Alamanni.
This people, defeated at Scarpona (Charpeigne) and Catelauni (Châlons-en-Champagne) by Jovinus, were driven back to the German bank of the Rhine, and checked for a while by a chain of military posts and fortresses. At the close of 367, however, they suddenly crossed the Rhine, attacked Moguntiacum (Mainz) and plundered the city. Valentinian attacked them at Solicinium (Sulz in the Neckar valley or Schwetzingen) with a large army, and defeated them with great slaughter, but his own losses were so considerable that he abandoned the idea of following up his success.
Later, in 374, he made peace with their king, Macrianus, who from that time remained a true friend of the Romans. The next three years he spent at Trier, which he chiefly made his headquarters, organizing the defence of the Rhine frontier, and personally superintending the construction of numerous forts.
During his reign the coasts of Gaul were harassed by the Saxon pirates, with whom the Picts and Scots of northern Britain joined hands, and ravaged the island from the wall of Antoninus to the shores of Kent. In 368 Theodosius was sent to drive back the invaders; in this he was completely successful, and established a new British province, called Valentia, in honour of the emperor.
In Africa the Moorish prince, Firmus, raised the standard of revolt, being joined by the provincials, who had been rendered desperate by the cruelty and extortions of Count Romanus, the military governor. The services of Theodosius were again requisitioned. He landed in Africa with a small band of veterans, and Firmus, to avoid being taken prisoner, committed suicide.
In 374 the Quadi, a German tribe in what is now Moravia and Slovakia, resenting the erection of Roman forts to the north of the Danube in what they considered to be their own territory, and further exasperated by the treacherous murder of their king, Gabinius, crossed the river and laid waste the province of Pannonia. The emperor in April of the following year entered Illyricum with a powerful army, but during an audience to an embassy from the Quadi at Brigetio on the Danube (near Komarom in Hungary) he suffered a burst blood vessel in the skull while angrily yelling at the people gathered, later dying on November 17, 375, from this injury.
His general administration seems to have been thoroughly honest and able, in some respects beneficent. If he was hard and exacting in the matter of taxes, he spent them in the defence and improvement of his dominions, not in idle show or luxury. Though himself a plain and almost illiterate soldier, he was a founder of schools, and he also provided medical attendance for the poor of Rome, by appointing a physician for each of the fourteen districts of the city.
He was an orthodox Christian, but he permitted absolute religious freedom to all his subjects. Against all abuses, both civil and ecclesiastical, he steadily set his face, even against the increasing wealth and worldliness of the clergy. His chief flaw was his temper, which at times was frightful, and showed itself in its full fierceness in the punishment of persons accused of witchcraft, fortune-telling or magical practices.