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
From: The History of Rome, by Theodor Mommsen
Translated with the sanction of the author by William Purdie Dickson
Caesar Takes the Offensive
Under these circumstances the war opened at the beginning of January 705. Of troops capable of marching Caesar had not more than a legion--5000 infantry and 300 cavalry--at Ravenna, which was by the highway some 240 miles distant from Rome; Pompeius had two weak legions--7000 infantry and a small squadron of cavalry-- under the orders of Appius Claudius at Luceria, from which, likewise by the highway, the distance was just about as great to the capital. The other troops of Caesar, leaving out of account the raw divisions of recruits still in course of formation, were stationed, one half on the Saone and Loire, the other half in Belgica, while Pompeius' Italian reserves were already arriving from all sides at their rendezvous; long before even the first of the Transalpine divisions of Caesar could arrive in Italy, a far superior army could not but be ready to receive it there.
It seemed folly, with a band of the strength of that of Catilina and for the moment without any effective reserve, to assume the aggressive against a superior and hourly-increasing army under an able general; but it was a folly in the spirit of Hannibal. If the beginning of the struggle were postponed till spring, the Spanish troops of Pompeius would assume the offensive in Transalpine, and his Italian troops in Cisalpine, Gaul, and Pompeius, a match for Caesar in tactics and superior to him in experience, was a formidable antagonist in such a campaign running its regular course. Now perhaps, accustomed as he was to operate slowly and surely with superior masses, he might be disconcerted by a wholly improvised attack; and that which could not greatly discompose Caesar's thirteenth legion after the severe trial of the Gallic surprise and the January campaign in the land of the Bellovaci,(14)--the suddenness of the war and the toil of a winter campaign--could not but disorganize the Pompeian corps consisting of old soldiers of Caesar or of ill-trained recruits, and still only in the course of formation.
14. Cf. V. VII. With the Bellovaci
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