 After his Mauretanian campaign , Maximian returned to the north of Italy , living a life of leisure in palaces in Milan and <unk> , and leaving warfare to his subordinate Constantius . Maximian was more aggressive in his relationship with the Senate than Constantius , and Lactantius contends that he terrorized senators , to the point of falsely charging and subsequently executing several , including the prefect of Rome in 301 / 2 . In contrast , Constantius kept up good relations with the senatorial aristocracy and spent his time in active defense of the empire . He took up arms against the Franks in 300 or 301 and in 302 – while Maximian was resting in Italy – continued to campaign against Germanic tribes on the Upper Rhine . 
