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
In recitative poetry metrical annals after the model of those
of Ennius seem not to have been wanting; but they were perhaps
sufficiently criticised by that graceful vow of his mistress
of which Catullus sings--that the worst of the bad heroic poems
should be presented as a sacrifice to holy Venus, if she would only
bring back her lover from his vile political poetry to her arms.
Lucretius
Indeed in the whole field of recitative poetry at this epoch
the older national-Roman tendency is represented only by a single work
of note, which, however, is altogether one of the most important
poetical products of Roman literature. It is the didactic poem
of Titus Lucretius Carus (655-699) "Concerning the Nature of Things,"
whose author, belonging to the best circles of Roman society,
but taking no part in public life whether from weakness of health
or from disinclination, died in the prime of manhood shortly before
the outbreak of the civil war. As a poet he attached himself
decidedly to Ennius and thereby to the classical Greek literature.