From the first Gallic war to the burning of Rome, 390, the Gauls had repeated their attacks in 360 and 348, even to the conclusion of the peace in 336. But in the latter part of the Samnite war, a formidable confederacy having taken place among the Italian tribes, some of the Gauls enlisted as mercenaries in the service of the Etruscans, while others allied themselves to the Samnites. This led them to take part in these wars in 306, 302, and 292, until they were obliged, together with the Etruscans, to sue for peace in 284, before which time the Romans had sent a colony into their country, near Sena. This peace lasted till 238, when it was disturbed by the incursion of the transalpine Gauls; without, however, their coming to any war with Rome. But in 232, the proposition of Flaminius the tribune, (_lex Flaminia_), to divide the lands conquered from the Senones, became the cause of new disturbances. Upon this occasion, the Gauls entered into an alliance with their transalpine countrymen, the Gaesates on the Rhone, who had been accustomed to engage as mercenaries. These having crossed the Alps, the dreadful war of six years (226-220) began, in which, after defeating the Gauls near Clusium, 225, the Romans pursued them into their own territory, and encamped upon the Po, 223. The Gauls having been again completely overthrown by Marcellus, were obliged to sue for peace; when the Roman colonies of Placentia and Cremona were established. The number of men capable of bearing arms in all Italy subject to the Romans during this war amounted to 800,000. 6. Before this storm was totally appeased, in which it is probable that Carthaginian policy was not altogether inactive, Hannibal had obtained the chief command in Spain. From the reproach of having first begun the war, he and his party cannot be cleared; Rome, in the situation she then was, could hardly desire it; he however who strikes the first blow is not always the real aggressor. The plan of Hannibal was the destruction of Rome; and by making Italy the principal seat of the war, he necessarily turned the scale in his favour; because Rome, obliged to defend herself, left to him all the advantages of attack. The preparations she made for defence, show that it was not believed possible he could execute his enterprise by the route which he took.