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
But the mutiny of the troops stationed in Rhegium--one of the legions levied from the Campanian subjects of Rome under a Campanian captain Decius--deprived the Romans of that important town. It was not, however, transferred to the hands of Pyrrhus. While on the one hand the national hatred of the Campanians against the Romans undoubtedly contributed to produce this military insurrection, it was impossible on the other hand that Pyrrhus, who had crossed the sea to shield and protect the Greeks, could receive as his allies troops who had put to death their Rhegine hosts in their own houses.
Thus they remained isolated, in close league with their kinsmen and comrades in crime, the Mamertines, that is, the Campanian mercenaries of Agathocles, who had by similar means gained possession of Messana on the opposite side of the straits; and they pillaged and laid waste for their own behoof the adjacent Greek towns, such as Croton, where they put to death the Roman garrison, and Caulonia, which they destroyed.
On the other hand the Romans succeeded, by means of a weak corps which advanced along the Lucanian frontier and of the garrison of Venusia, in preventing the Lucanians and Samnites from uniting with Pyrrhus; while the main force--four legions as it would appear, and so, with a corresponding number of allied troops, at least 50,000 strong--marched against Pyrrhus, under the consul Publius Laevinus.
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