DN VALENS PF AVG, Diademed, draped and cuirassed bust right / SECVRITAS REIPVBLICAE, Victory walking left with wreath, marks in fields, mintmark in exergue. 18mm, 2.91 grams. Siscia mint. RIC 7. 

Valens was Eastern Roman emperor from 364 to 378 AD, ruling alongside his brother Valentinian I, who governed the Western Empire. Valens is best known for his support of Arian Christianity, which put him at odds with Nicene Christians, and for his struggles against Gothic incursions along the Danube frontier. His reign ended disastrously at the Battle of Adrianople, where he was defeated and killed by the Goths - an event often seen as a major turning point in the decline of the Roman Empire.