Founded by Augustus around 27 B.C., the elite Praetorian Guard was tasked with the protection of the emperor and his family. As the centuries unfolded, however, Praetorian soldiers served not only as protectors and enforcers but also as powerful political players. Fiercely loyal to some emperors, they vied with others and ruthlessly toppled those who displeased them, including Caligula, Nero, Pertinax, and many more. Guy de la Bédoyère provides a compelling first full narrative history of the Praetorians, whose dangerous ambitions ceased only when Constantine permanently disbanded them.