Follis - Valens SECVRITAS REIPVBLICAE, Siscia

Valens became co-emperor in 364 when his brother Valentinian I, having seized power after Jovian's sudden death, needed a trusted partner to hold the East while he managed the Rhine frontier. The Siscia mint — modern Sisak in Croatia — was one of the most productive western mints of the late fourth century, and issues from this early period of Valens' reign predate his disastrous eastern campaigns by over a decade. He would die at Adrianople in 378, the first Roman emperor killed in battle since Decius, and the defeat effectively ended Roman military dominance of the Balkans.