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
It is no matter of wonder therefore that the Achaeans settled in
Italy exercised less influence on its civilization than the other
Greek settlements. An agricultural people, they had less occasion
than those engaged in commerce to extend their influence beyond
their political bounds.
Within their own dominions they enslaved
the native population and crushed the germs of their national
development as Italians, while they refused to open up to them
by means of complete Hellenization a new career. In this way the
Greek characteristics, which were able elsewhere to retain a vigorous
vitality notwithstanding all political misfortunes, disappeared
more rapidly, more completely, and more ingloriously in Sybaris
and Metapontum, in Croton and Posidonia, than in any other region;
and the bilingual mongrel peoples, that arose in subsequent times
out of the remains of the native Italians and Achaeans and the more
recent immigrants of Sabellian descent, never attained any real
prosperity. This catastrophe, however, belongs in point of time
to the succeeding period.