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
While the Celtic and Ligurian population of these regions
was thus in the course of losing its nationality, and was languishing
and pining withal under a political and economic oppression,
the intolerable nature of which is sufficiently attested by their
hopeless insurrections, the decline of the native population here
went hand in hand with the naturalizing of the same higher culture
which we find at this period in Italy.
Aquae Sextiae and still
more Narbo were considerable townships, which might probably be
named by the side of Beneventum and Capua; and Massilia, the best
organized, most free, most capable of self-defence, and most
powerful of all the Greek cities dependent on Rome, under its
rigorous aristocratic government to which the Roman conservatives
probably pointed as the model of a good urban constitution,
in possession of an important territory which had been considerably
enlarged by the Romans and of an extensive trade, stood by the side
of those Latin towns as Rhegium and Neapolis stood in Italy
by the side of Beneventum and Capua.