In this new edition Pat Southern examines the anarchic era of the soldier Emperors that preceded the crisis of AD 260, and the reigns of underrated and maligned Emperors such as Gallienus, Probus and Aurelian, whose determination and hard work reunited the Empire. The successes and failures of these rulers, and the role of armies and civilians, are re-assessed in this revised and expanded edition of The Roman Empire from Severus to Constantine, which incorporates the latest thinking of modern scholars and has been extended to cover Constantine, whose reign transformed the Empire into a Christian state. This is a crucial volume for students of this fascinating period in Roman history.