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 a seasonable and decisive victory of Rullianus, the battle at the Vadimonian lake which long lived in the memory of the people, converted an imprudent enterprise into a celebrated feat of heroism and broke the resistance of the Etruscans.
Unlike the Samnites who had now for eighteen years maintained the unequal struggle, three of the most powerful Etruscan towns--Perusia, Cortona, and Arretium--consented after the first defeat to a separate peace for three hundred months (444), and after the Romans had once more beaten the other Etruscans near Perusia in the following year, the Tarquinienses also agreed to a peace of four hundred months (446); whereupon the other cities desisted from the contest, and a temporary cessation of arms took place throughout Etruria.
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Reference address : https://www.ellopos.net/elpenor/rome/2-06-italians-rome.asp?pg=22