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
Yet they might, perhaps, have got over this,
and after the manner of oligarchs, when they had no capable candidate,
have filled the place with some sort of makeshift, if Pompeius had
merely desired the command and had not demanded it at the head
of an army. He had already lent a deaf ear to the injunctions
of Catulus that he should dismiss the army; it was at least doubtful
whether those of the senate would find a better reception,
and the consequences of a breach no one could calculate--
the scale of aristocracy might very easily mount up, if the sword
of a well-known general were thrown into the opposite scale.
So the majority resolved on concession. Not from the people,
which constitutionally ought to have been consulted in a case
where a private man was to be invested with the supreme magisterial
power, but from the senate, Pompeius received proconsular authority
and the chief command in Hither Spain; and, forty days after he had
received it, crossed the Alps in the summer of 677.