Rome, 4th century AD. The Empire is now too vast to be ruled by a single man. For the first time, it is decided to divide it into two. Valentinian, an excellent general, rules the Western Empire. Valens, his brother, a far less talented man, governs the Eastern Empire. After receiving a delegation from the barbarian chiefs, Valentinian plunges into one of his habitual, violent rages. On this occasion, his body gives up: suffering a brain hemorrhage, he collapses and dies during the night. His son, Gratian, replaces him as head of the Western Empire at the worst possible moment. The Goths, driven from their own lands by the Huns, cross the Empire’s frontiers. Valens, Emperor of the East, brings his army home to Adrianople to confront the Goths. Rather than wait for reinforcements from the West, he decides to deal with the problem alone. Valentinian would have scant difficulty in slaughtering the Goth army, but Valens, because of his incompetence, presents the barbarians with an unlikely victory on a plate. The Romans will never manage to drive the Goths from their Empire. Worse, the Goths will sack Rome in 410 AD, and the Western Roman Empire will disappear in 476. A stroke is at the origin of the destruction of the most powerful empire ever known.