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
Beginning of the War
Thus the war began in 680 at all points. It was a misfortune for Mithradates, that at the very moment of his declaring war the Sertorian struggle reached its crisis, by which one of his principal hopes was from the outset destroyed, and the Roman government was enabled to apply its whole power to the maritime and Asiatic contest. In Asia Minor on the other hand Mithradates reaped the advantages of the offensive, and of the great distance of the Romans from the immediate seat of war. A considerable number of cities in Asia Minor opened their gates to the Sertorian propraetor who was placed at the head of the Roman province, and they massacred, as in 666, the Roman families settled among them: the Pisidians, Isaurians, and Cilicians took up arms against Rome.
The Romans for the moment had no troops at the points threatened. Individual energetic men attempted no doubt at their own hand to check this mutiny of the provincials; thus on receiving accounts of these events the young Gaius Caesar left Rhodes where he was staying on account of his studies, and with a hastily-collected band opposed himself to the insurgents; but not much could be effected by such volunteer corps. Had not Deiotarus, the brave tetrarch of the Tolistobogii--a Celtic tribe settled around Pessinus--embraced the side of the Romans and fought with success against the Pontic generals, Lucullus would have had to begin with recapturing the interior of the Roman province from the enemy.
But even as it was, he lost in pacifying the province and driving back the enemy precious time, for which the slight successes achieved by his cavalry were far from affording compensation. Still more unfavourable than in Phrygia was the aspect of things for the Romans on the north coast of Asia Minor. Here the great Pontic army and the fleet had completely mastered Bithynia, and compelled the Roman consul Cotta to take shelter with his far from numerous force and his ships within the walls and port of Chalcedon, where Mithradates kept them blockaded.
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