The Praetorian Guard: The History of the Roman Emperors' Imperial Bodyguards

A member of Caesar's extended family, Gaius Marius, was the military visionary who had restructured the legions and extended the privileges of land ownership and citizenship to legionaries on condition of successful completion of a fixed term of service. Marius made the army more professional and helped propel Rome's expansion, but those same reforms eventually made the legions fiercely loyal to their individual generals rather than the state, which would make Caesar's seizure of power pos...