Outside the Po valley, however, Italy was in a very different state; southern Italy and much of central Italy preserved its ancient organisation almost undisturbed; the Exarchate of Ravenna, the _Ducatus Romanus_, and the southern peninsulas of Apulia and Bruttium remained unchanged down to the ninth century. Records show us in the neighbourhood of Rome the old social organisation of the land, in domains inhabited by _coloni_, and owned by Roman church corporations, or absentee proprietors, at a time when in the northern plains the feudal system of the semi-independent dukes, each surrounded by their land-holding _comites_, was in full operation. In organisation, no less than in blood, northern Italy and southern Italy were fatally sundered, and two nations differing in all their usages of life and manners of thought were growing up. The parts of Italy which remained under the imperial sceptre and preserved their ancient social and political organisation were strangely scattered. In the reign of Maurice (582-602) the emperor was still obeyed in eight regions. First was the Istrian peninsula, and the marsh and lagoon islands of the Venetian coast, with the strong cities of Padua and Mantua thrust inland like a wedge into the side of Lombardy. Second came the Ligurian coast with the city of Genoa, crushed in between the Apennines and the sea; its rugged valleys and cliffs did not yet tempt the Lombards out of their smiling plain to court the neighbourhood of the sea, for the Lombards were essentially unmaritime. [Sidenote: Imperial possessions in Italy.] Third is found the tract of land round Ravenna, the Exarchate, as it now became called—a title which it shared for a space with Africa, where exarchs also reigned. The Exarchate stretched along the coast of the Adriatic, from the delta of the Po up to the gates of Rimini, reaching as far inland as the Apennines, and comprising the whole southern half of the ancient province of Æmilia. Farther down the coast lay the fourth imperial district, from Rimini to Ancona, which was often called the Pentapolis and the Decapolis, from two groups of five and ten cities respectively which it contained.[30] In Umbria lay a fifth detached district where the emperor was still acknowledged; it centred around Perugia, and was much hemmed in by the Lombard duchies of Chiusi and Spoleto, but it stretched out one horn toward the Pentapolis on the north, and the other toward Rome on the south. The sixth district was the Roman territory, now known as the _Ducatus Romanus_, from the _dux_ who acted as civil governor in the ancient city in subordination to the exarch at Ravenna. The Roman duchy reached from Civita Vecchia to Terracina, and from the Apennines to the sea, taking in the southern corner of Etruria, and well-nigh the whole of Latium. It was cut off by the Lombard town of Capua from the duchy of Naples, a narrow coast-strip containing the towns of Naples and Amalfi, and ruled by a duke resident in the larger