There were not about him at that time above three hundred horse and five thousand foot; for the rest of his army, which was left behind the Alps, was to be brought after him by officers who had received orders for that purpose. But he thought the first motion towards the design which he had on foot did not require large forces at present, and that what was wanted was to make this first step suddenly, and so to astound his enemies with the boldness of it; as it would be easier, he thought, to throw them into consternation by doing what they never anticipated than fairly to conquer them, if he had alarmed them by his preparations. And therefore he commanded his captains and other officers to go only with their swords in their hands, without any other arms, and make themselves masters of Ariminum, a large city of Gaul, with as little disturbance and bloodshed as possible. He committed the care of these forces to Hortensius, and himself spent the day in public as a stander-by and spectator of the gladiators, who exercised before him. A little before night he attended to his person, and then went into the hall, and conversed for some time with those be had invited to supper, till it began to grow dusk, when he rose from table and made his excuses to the company, begging them to stay till he came back, having already given private directions to a few immediate friends that they should follow him, not all the same way, but some one way, some another. He himself got into one of the hired carriages, and drove at first another way, but presently turned towards Ariminum. When he came to the river Rubicon, which parts Gaul within the Alps from the rest of Italy, his thoughts began to work, now he was just entering upon the danger, and he wavered much in his mind when he considered the greatness of the enterprise into which he was throwing himself. He checked his course and ordered a halt, while he revolved with himself, and often changed his opinion one way and the other, without speaking a word. This was when his purposes fluctuated most; presently he also discussed the matter with his friends who were about him (of which number Asinius Pollio was one), computing how many calamities his passing that river would bring upon mankind, and what a relation of it would be transmitted to posterity. At last, in a sort of passion, casting aside calculation, and abandoning himself to what might come, and using the proverb frequently in their mouths who enter upon dangerous and bold attempts, "The die is cast," with these words he took the river. Once over, he used all expedition possible, and before it was day reached Ariminum and took it. It is said that the night before he passed the river he had an impious dream, that he was unnaturally familiar with his own mother.
As soon as Ariminum was taken, wide gates, so to say, were thrown open, to let in war upon every land alike and sea, and with the limits of the province, the boundaries of the laws were transgressed. Nor would one have thought that, as at other times, the mere men and women fled from one town of Italy to another in their consternation, but that the very towns themselves left their sites and fled for succour to each other. The city of Rome was overrun, as it were, with a deluge, by the conflux of people flying in from all the neighbouring places. Magistrates could not longer govern, nor the eloquence of any orator quiet it; it was all but suffering shipwreck by the violence of its own tempestuous agitation. The most vehement contrary passions and impulses were at work everywhere. Nor did those who rejoiced at the prospect of the change altogether conceal their feelings, but when they met, as in so great a city they frequently must, with the alarmed and dejected of the other party, they provoked quarrels by their bold expressions of confidence in the event. Pompey, sufficiently disturbed of himself, was yet more perplexed by the clamours of others; some telling him that he justly suffered for having armed Caesar against himself and the government;others blaming him for permitting Caesar to be insolently used by Lentulus, when he made such ample concessions, and offered such reasonable proposals towards an accommodation. Favonius bade him now stamp upon the ground; for once talking big in the senate, he desired them not to trouble themselves about making any preparations for the war, for that he himself, with one stamp of his foot, would fill all Italy with soldiers. Yet still Pompey at that time had more forces than Caesar; but he was not permitted to pursue his own thoughts, but, being continually disturbed with false reports and alarms, as if the enemy was close upon him and carrying all before him, he gave way and let himself be borne down by the general cry.
He put forth an edict declaring the city to be in a state of anarchy, and left it with orders that the senate should follow him, and that no one should stay behind who did not prefer tyranny to their country and liberty.
The consuls at once fled, without making even the usual sacrifices; so did most of the senators, carrying off their own goods in as much haste as if they had been robbing their neighbours.
Some, who had formerly much favoured Caesar's cause, in the prevailing alarm quitted their own sentiments, and without any prospect of good to themselves were carried along by the common stream. It was a melancholy thing to see the city tossed in these tumults, like a ship given up by her pilots, and left to run, as chance guides her, upon any rock in her way. Yet, in spite of their sad condition people still esteemed the place of their exile to be their country for Pompey's sake, and fled from Rome, as if it had been Caesar's camp.
Labienus even, who had been one of Caesar's nearest friends, and his lieutenant, and who had fought by him zealously in the Gallic wars, now deserted him, and went over to Pompey. Caesar sent all his money and equipage after him, and then sat down before Corfinium, which was garrisoned with thirty cohorts under the command of Domitius.