Please note that Mommsen uses the AUC chronology (Ab Urbe Condita), i.e. from the founding of the City of Rome. You can use this reference table to have the B.C. dates
From: The History of Rome, by Theodor Mommsen
Translated with the sanction of the author by William Purdie Dickson
Before we describe the political organization under which the Italy which was thus united was governed on the part of Rome, it remains that we should glance at the maritime relations that subsisted in the fourth and fifth centuries. At this period Syracuse and Carthage were the main competitors for the dominion of the western waters. On the whole, notwithstanding the great temporary successes which Dionysius (348-389), Agathocles (437-465), and Pyrrhus (476-478) obtained at sea, Carthage had the preponderance and Syracuse sank more and more into a naval power of the second rank.
The maritime importance of Etruria was wholly gone;(6) the hitherto Etruscan island of Corsica, if it did not quite pass into the possession, fell under the maritime supremacy, of the Carthaginians. Tarentum, which for a time had played a considerable part, had its power broken by the Roman occupation. The brave Massiliots maintained their ground in their own waters; but they exercised no material influence over the course of events in those of Italy. The other maritime cities hardly came as yet into serious account.
6. Cf. II. IV. Victories of Salamis and Himera, and Their Effects
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