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
This induced the Gauls to return homeward. Their dexterously-contrived plan for preventing the union of the two Roman armies and annihilating the weaker in detail, had only been partially successful; now it seemed to them advisable first of all to place in security their considerable booty. For the sake of an easier line of march they proceeded from the district of Chiusi, where they were, to the level coast, and were marching along the shore, when they found an unexpected obstacle in the way.
It was the Sardinian legions, which had landed at Pisae; and, when they arrived too late to obstruct the passage of the Apennines, had immediately put themselves in motion and were advancing along the coast in a direction opposite to the march of the Gauls. Near Telamon (at the mouth of the Ombrone) they met with the enemy. While the Roman infantry advanced with close front along the great road, the cavalry, led by the consul Gaius Atilius Regulus in person, made a side movement so as to take the Gauls in flank, and to acquaint the other Roman army under Papus as soon as possible with their arrival.
A hot cavalry engagement took place, in which along with many brave Romans Regulus fell; but he had not sacrificed his life in vain: his object was gained. Papus became aware of the conflict, and guessed how matters stood; he hastily arrayed his legions, and on both sides the Celtic host was now pressed by Roman legions.
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