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
accordance with this plan they ought above all, when the war had been
practically opened by Hannibal's attack on Saguntum in the beginning
of 535, to have thrown a Roman army into Spain before the town fell;
but they neglected the dictates of interest no less than of honour.
For eight months Saguntum held out in vain: when the town passed into
other hands, Rome had not even equipped her armament for landing in
Spain.
The country, however, between the Ebro and the Pyrenees was
still free, and its tribes were not only the natural allies of the
Romans, but had also, like the Saguntines, received from Roman
emissaries promises of speedy assistance. Catalonia may be reached by
sea from Italy in not much longer time than from Cartagena by and: had
the Romans started, like the Phoenicians, in April, after the formal
declaration of war that had taken place in the interval, Hannibal
might have encountered the Roman legions on the line of the Ebro.