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
Second Year of the War - Etruria and Umbria Tranquillized
On the strength of these concessions to the wavering communities, the
Romans resumed with fresh courage the conflict against the insurgent
districts. They had pulled down as much of the existing political
institutions as seemed necessary to arrest the extension of the
conflagration; the insurrection thenceforth at least spread no
farther.
In Etruria and Umbria especially, where it was just
beginning, it was subdued with singular rapidity, still more, probably,
by means of the Julian law than through the success of the Roman arms.
In the former Latin colonies, and in the thickly-peopled region of the
Po, there were opened up copious and now trustworthy sources of aid:
with these, and with the resources of the burgesses themselves, they
could proceed to subdue the now isolated conflagration. The two former
commanders-in-chief returned to Rome, Caesar as censor elect, Marius
because his conduct of the war was blamed as vacillating and slow, and
the man of sixty-six was declared to be in his dotage.