Which territories were administered by Maximian in the tetrarchy?

In the system of the tetrarchy established by Diocletian, the administration of the empire was divided among four rulers, each with a specific sector of operation.1

As one of the two Augusti, Maximian was responsible for the western portion of the empire. His primary administrative territories included:2

• Italy321
• Sicily2
• Africa321

While Maximian initially held broader authority in the West, the appointment of Constantius I Chlorus as his Caesar in 293 led to a further division of duties. Constantius took direct charge of Gaul, Spain, and Britain, while Maximian maintained his governance over Italy, Sicily, and Africa. Throughout his tenure, Maximian resided primarily in Milan to oversee these regions and defend against potential invasions.321