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
The Hellenism of Euripides flowed to Rome through very various
channels, and probably produced a speedier and deeper effect there
by indirect means than in the form of direct translation. The tragic
drama in Rome was not exactly later in its rise than the comic;(39)
but the far greater expense of putting a tragedy on the stage--which
was undoubtedly felt as a consideration of moment, at least during the
Hannibalic war--as well as the nature of the audience(40) retarded the
development of tragedy.
In the comedies of Plautus the allusions to
tragedies are not very frequent, and most references of this kind may
have been taken from the originals. The first and only influential
tragedian of this epoch was the younger contemporary of Naevius
and Plautus, Quintus Ennius (515-585), whose pieces were already
travestied by contemporary comic writers, and were exhibited and
declaimed by posterity down to the days of the empire.