When Rome had asserted her supremacy over the greater part of Sicily at the close of the first Punic war, a new problem in organisation was presented to her. She held, perhaps rightly, that these new dependencies, with their transmarine position, fickle politics, and in some cases Carthaginian sympathies, could not safely be included in the military symmachy of Italy; so she substituted tribute for military service, placed the command of the cities of a wide district under the guidance of the personal _imperium_, and created the first permanent external department of administration (_provincia_). The government which had been adopted for Hellenic cities was still more necessary for the barbarians of Spain, a country which Rome had not sought but which military exigencies alone warned her not to leave. The recognition of Empire in the West was rapid and easy, for the effective government of Italy seemed to involve the control of the Tyrrhenian Sea. The Senate showed greater hesitancy in accepting a similar Adriatic policy, and declined to recognise that Rome had permanent interests even in eastern Europe of a magnitude that should lead to Empire. War followed war, Greece was once and Macedon twice at her feet, but on every occasion she declined to annex. It was not until experience had proved the costliness and the danger of a protectorate that in 146 B.C. Macedonia was recognised as a province with Achaea as its annexe. The troublesome relations with Carthage had meanwhile ended in war and annexation, and what had hitherto been rather a distant problem—Rome’s relations with the potentates of Asia—became, as the years rolled on and as Roman trade struck deeper roots in the East, one of paramount concern. The history of eastern Europe was repeated in Asia, and although Rome had already a foothold in Anatolia through her acceptance of the kingdom of Pergamus, the death-blow to the protectorate system in these regions was first struck by Pompeius’ organisation of the East at the close of the Mithridatic wars (65-63). Further extensions in the West and North, which resulted in the conquest of further Spain and of Gaul, were due to the enterprise of individual commanders, or to the search for a frontier which should be a permanent protection against barbarian invasion; and at the close of the Republic the list of Roman provinces had risen to fifteen.[1487]