The Ugliness of the Roman Empire

In terms of the sheer ugliness of the situation an emperor walked into upon dawning the purple, there were few situations uglier than the one Jovian walked into. It's easy to demand vigor and resiliency when you're safely tucked thousands of miles away at the imperial capital. Much harder when you're actually standing there, plausibly facing total annihilation. The new emperor at first attempted to continue the retreat towards Armenia, but the loss of Jovian had destroyed morale so he did what he no doubt felt he had to do.