Val'entin'ian I, a Roman emperor. On the death of Jovian, in 364, he was chosen emperor by the army, despite his humble origin. He shared the Empire with his brother Valens, who ruled the East, Valentinian reserving the Western provinces for himself. Although chiefly occupied throughout his reign in repelling invasions of the barbarians, he proved himself a firm and just ruler, and he abolished many abuses. His sons, Gratianus and Valentinian II, succeeded him.