The Danubian region, to all appearance up to 727 {27.} administered along with Upper Italy, became then, on the reorganisation of the empire, an independent administrative district, Illyricum, under a governor of its own. It consisted of Dalmatia, with the country behind it, as far as the Drin--while the coast farther to the south had for long belonged to the province of Macedonia--and of the Roman possessions in the land of the Pannonians on the Save. The region between the Haemus and the Danube as far as the Black Sea, which Crassus had shortly before brought into dependence on the empire, as well as Noricum and Raetia, stood in a relation of clientship to Rome, and so did not belong as such to this province, but withal were primarily dependent on the governor of Illyricum. Thrace, north of the Haemus, still by no means pacified, fell, from a military point of view, to the same district. It was a continued effect of the original organisation, and one which subsisted down to a late period, that the whole region of the Danube from Raetia to Moesia was comprehended as a customs-district under the name Illyricum in the wider sense. Legions were stationed only in Illyricum proper, in the other districts there were probably no imperial troops at all, or at the utmost small detachments; the chief command was held by the proconsul of the new province coming from the senate; while the soldiers and officers were, as a matter of course, imperial. It attests the serious character of the offensive beginning after the conquest of Raetia, that in the first instance the co-ruler Agrippa took over the command in the region of the Danube, to whom the proconsul of Illyricum had to become _de iure_ subordinate; and then, when Agrippa's sudden death in the spring of 742 {12.} broke down this combination, Illyricum in the following year passed into imperial administration, and the imperial generals obtained the chief commands in it. Soon three military centres were here formed, which thereupon brought about the administrative division of the Danubian region into three parts. The small principalities in the territory conquered by Crassus gave place to the province of Moesia, the governor of which henceforth, in what is now Servia and Bulgaria, guarded the frontier against the Dacians and Bastarnae. In what had hitherto been the province of Illyricum, a part of the legionaries was posted on the Kerka and the Cettina, to keep in check the still troublesome Dalmatians. The chief force was stationed in Pannonia, on what was then the boundary of the empire, the Save. This distribution of the legions and organisation of the provinces cannot be fixed with chronological precision; probably the serious wars which were waged simultaneously against the Pannonians and the Thracians, of which we have immediately to speak, led in the first instance to the institution of the governorship of Moesia, and it was not till some