Procopius was a Roman usurper against Valens and a member of the Constantinian dynasty. According to some historians, he was a native of Cilicia. He took part in the Emperor Julian's campaign against the Persian Empire in 363. At the time of Julian's death, there were rumors that he had intended Procopius to be his successor, but when Jovian was elected emperor by the Roman army, Procopius went into hiding to preserve his life.
After Jovian's death, Valentinian I shared the purple with his brother Valens. Procopius immediately moved to declare himself emperor. He bribed two legions which were then resting at Constantinople to support his efforts and took control of the imperial city. Shortly after this, he proclaimed himself Emperor on September 28, 365, and quickly took control of the provinces of Thrace, and later Bithynia.
This centenionalis of Procopius issued from Constantinople mint. It depicts pearl-diademed, draped, cuirassed bust of Procopius left on its obverse face. The reverse of a coin represents Procopius standing facing, head right, labarum in the right hand, resting left on grounded shield, Christogram before the face, the small object on the ground to left.
Image Source: Heritage Auctions