Maxentius and Maximian - A History of the Roman Empire

Maxentius and his father, maximian, resided together in rome. When they discovered the assumptions the other had been making, they began to feud. With his father out of the way, maxentius probably hoped things would calm down a bit. But almost as soon as the old man was gone, word came up to rome that demidius alexander, the vicar of africa, had had himself proclaimed emperor by the troops at carthage. It is kind of surprising that the eastern augustus did not just have the old man executed straightway for killing his western counterpart.