These repeated repulses which Pompeius met with in the senate and, what was worse, had to acquiesce in without retaliation, were naturally regarded - come from what side they would - by the public at large as so many victories of the republicans and defeats of the regents generally; the tide of republican opposition was accordingly always on the increase. Already the elections for 698 had gone but partially according to the minds of the dynasts; Caesar's candidates for the praetorship, Publius Vatinius and Gaius Alfius, had failed, while two decided adherents of the fallen government, Gnaeus Lentulus Marcellinus and Gnaeus Domitius Calvinus, had been elected, the former as consul, the latter as praetor.
But for 699 there even appeared as candidate for the consulship Lucius Domitius Ahenobarbus, whose election it was difficult to prevent owing to his influence in the capital and his colossal wealth, and who, it was sufficiently well known, would not be content with a concealed opposition. The comitia thus rebelled; and the senate chimed in. It solemnly deliberated over an opinion, which Etruscan soothsayers of acknowledged wisdom had furnished respecting certain signs and wonders at its special request. The celestial revelation announced that through the dissension of the upper classes the whole power over the army and treasure threatened to pass to one ruler, and the state to incur loss of freedom - it seemed that the gods pointed primarily at the proposal of Gaius Messius. The republicans soon descended from heaven to earth. The law as to the domain of Capua and the other laws issued by Caesar as consul had been constantly described by them as null and void, and an opinion had been expressed in the senate as early as Dec. 697 that it was necessary to cancel them on account of their informalities. On the 6th April 698 the consular Cicero proposed in a full senate to put the consideration of the Campanian land distribution in the order of the day for the 15th May. It was the formal declaration of war; and it was the more significant, that it came from the mouth of one of those men who only show their colours when they think that they can do so with safety. Evidently the aristocracy held that the moment had come for beginning the struggle not with Pompeius against Caesar, but against the tyrannis generally. What would further follow might easily be seen. Domitius made no secret that he intended as consul to propose to the burgesses the immediate recall of Caesar from Gaul. An aristocratic restoration was at work; and with the attack on the colony of Capua the nobility threw down the gauntlet to the regents.
Caesar, although receiving from day to day detailed accounts of the events in the capital and, whenever military considerations allowed, watching their progress from as near a point of his southern province as possible, had not hitherto, visibly at least interfered in them. But now war had been declared against him as well as his colleague, in fact against him especially; he was compelled to act, and he acted quickly. He happened to be in the very neighbourhood; the aristocracy had not even found it advisable to delay the rupture, till he should have again crossed the Alps. In the beginning of April 698 Crassus left the capital, to concert the necessary measures with his more powerful colleague; he found Caesar in Ravenna. Thence both proceeded to Luca, and there they were joined by Pompeius, who had departed from Rome soon after Crassus (11 April), ostensibly for the purpose of procuring supplies of grain from Sardinia and Africa. The most noted adherents of the regents, such as Metellus Nepos the proconsul of Hither Spain, Appius Claudius the propraetor of Sardinia, and many others, followed them; a hundred and twenty lictors, and upwards of two hundred senators were counted at this conference, where already the new monarchical senate was represented in contradistinction to the republican.
In every respect the decisive voice lay with Caesar. He used it to re-establish and consolidate the existing joint rule on a new basis of more equal distribution of power of most importance in a military point of view, next to that of the two Gauls, were assigned to his two colleagues - that of the two Spains to Pompeius, that of Syria to Crassus; and these offices were to be secured to them by decree of the people for five years (700-704), and to be suitably provided for in a military and financial point of view. On the other hand Caesar stipulated for the prolongation of his command, which expired with the year 700, to the close of 705, as well as for the prerogative of increasing his legions to ten and of charging the pay for the troops arbitrarily levied by him on the state-chest. Pompeius and Crassus were moreover promised a second consulship for the next year (699) before they departed for their governorships, while Caesar kept it open to himself to administer the supreme magistracy a second time after the termination of his governorship in 706, when the ten years' interval legally requisite between two consulships should have in his case elapsed. The military support, which Pompeius and Crassus required for regulating the affairs of the capital all the more that the legions of Caesar originally destined for this purpose could not now be withdrawn from Transalpine Gaul, was to be found in new legions, which they were to raise for the Spanish and Syrian armies and were not to despatch from Italy to their several destinations until it should seem to themselves convenient to do so. The main questions were thus settled; subordinate matters, such as the settlement of the tactics to be followed against the opposition in the capital, the regulation of the candidatures for the ensuing years, and the like, did not long detain them. The great master of mediation composed the personal differences which stood in the way of an agreement with his wonted ease, and compelled the most refractory elements to act in concert.
An understanding befitting colleagues was reestablished, externally at least, between Pompeius and Crassus. Even Publius Clodius was induced to keep himself and his pack quiet, and to give no farther annoyance to Pompeius - not the least marvellous feat of the mighty magician.
That this whole settlement of the pending questions proceeded, not from a compromise among independent and rival regents meeting on equal terms, but solely from the good will of Caesar, is evident from the circumstances. Pompeius appeared at Luca in the painful position of a powerless refugee, who comes to ask aid from his opponent. Whether Caesar chose to dismiss him and to declare the coalition dissolved, or to receive him and to let the league continue just as it stood - Pompeius was in either view politically annihilated. If he did not in this case break with Caesar, he became the powerless client of his confederate. If on the other hand he did break with Caesar and, which was not very probable, effected even now a coalition with the aristocracy, this alliance between opponents, concluded under pressure of necessity and at the last moment, was so little formidable that it was hardly for the sake of averting it that Caesar agreed to those concessions. A serious rivalry on the part of Crassus with Caesar was utterly impossible. It is difficult to say what motives induced Caesar to surrender without necessity his superior position, and now voluntarily to concede - what he had refused to his rival even on the conclusion of the league of 694, and what the latter had since, with the evident design of being armed against Caesar, vainly striven in different ways to attain without, nay against, Caesar's will - the second consulate and military power. Certainly it was not Pompeius alone that was placed at the head of an army, but also his old enemy and Caesar's ally throughout many years, Crassus; and undoubtedly Crassus obtained his respectable military position merely as a counterpoise to the new power of Pompeius. Nevertheless Caesar was a great loser, when his rival exchanged his former powerlessness for an important command. It is possible that Caesar did not yet feel himself sufficiently master of his soldiers to lead them with confidence to a warfare against the formal authorities of the land, and was therefore anxious not to be forced to civil war now by being recalled from Gaul; but whether civil war should come or not, depended at the moment far more on the aristocracy of the capital than on Pompeius, and this would have been at most a reason for Caesar not breaking openly with Pompeius, so that the opposition might not be emboldened by this breach, but not a reason for conceding to him what he did concede.