Church History, Book 5
The Death of Gratian and the Reign of Maximus
In the midst of his successes in war and his wise and prudent government, Gratian lost his life through a conspiracy. He left no sons to inherit the empire, only a brother, Valentinian, who bore the same name as their father and was quite a youth. So Maximus, despising the youth of Valentinian, seized the throne of the West.