On this date in 364AD, the none-too-distinguished son of a nouveau riche Pannonian rope salesman who had made it big in the army got his own shot at the brass ring.
His older brother, who had been conveniently present at the death of the previous emperor, had been proclaimed Augustus and, deciding that he needed help running the empire, now he appointed Valens as his co-emperor in the east.
Nominally governing from Constantinople, Valens mostly spent the next 14 years gallivanting about the Near East, racing from crisis to crisis. From a usurper in Constantinople to uppity Persians to playing politics in Armenia, he probably got all of five minutes' rest in the next fourteen years.
He is, of course, best known for losing both the battle and his head to marauding migratory Goths in the rolling fields outside Adrianople, marking what many consider the beginning of the end of the Western Empire.