Book excerpt: Conceived as a personal army for the emperor, the elite Praetorian Guard soon took over a wide range of powers in Rome, and thus from the very beginning made a much greater impact on the city's life than just as an imperial bodyguard. The Praetorians were in fact inseparable from the whole machinery of state, in some cases even making or breaking individual emperors. Sandra Bingham here offers a timely history of the Guard from its foundation by Augustus in 27 BCE to its disbandment by Constantine in CE 312. Topics covered include arms and insignia; the size, recruitment and command structure of the Guard; duration of service; the duties of individual soldiers and officers; and their families, daily lives and religion.