 Probably born about 160 AD, Marius Maximus’ military career began in the reign of Marcus Aurelius, when he was "Tribunus laticlavius" of the Legio XXII Primigenia.Around 178 to 180, he held the same rank in the Legio III Italica.During Marcus Aurelius’ reign, he was also one of the "quattuorviri viarum curandarum" (or officer in charge of the roads outside of the walls of Rome).