Answer
Ruling for 16 years, Gratian's reign marked a period of relative stability and prosperity for the Western Roman Empire. He successfully repelled numerous barbarian incursions, most notably the Alemanni at the Battle of Argentovaria in 378. However, his unwavering support for Christianity and preference for Germanic generals alienated the traditional Roman aristocracy, leading to his downfall and eventual assassination by the usurper Magnus Maximus in 383.