 The Lombards occupied northern Italy, largely unopposed.In order to face the mounting pressure, in the more distant provinces of the West, recently regained by Justinian I (r. 527–565), Emperor Maurice (r. 582–602) combined supreme civil and military authority in the person of an "exarch", forming the exarchates of Ravenna and Africa.These developments overturned the strict division of civil and military offices, which had been one of the cornerstones of the reforms of Diocletian (r. 284–305).