Valens (28 March 364 - 9 August 378CE). Valentinian named Flavius Julius Valens, his younger brother, Augustus in the east on March 28, 364. Valens was an undistinguished emperor with little military skill, but he successfully defeated the usurper, Procopius, and had him executed in 366. Valens, sometimes known as the Last True Roman, was killed together with two-thirds of his army, in the Battle of Adrianople which marked the beginning of the collapse of the Roman Empire.