Claudius I. was perhaps tempted into the invasion by his dislike of the cruel rites of Druidism, which, now that Gaul was Roman, had its main stronghold in British Mona. But Roman capitalists had for years been acquiring interests in the island; when the occupation was an accomplished fact, they settled down to bleed it in true usurers’ fashion, with disastrous results. It is probable that the formation of something like a British Empire close to Gaul, where the old times were not forgotten, and where a great revolt did actually break out a generation later, seemed an alarming phenomenon. Doubtless also there were plenty of ambitious soldiers and politicians anxious to prove to the sensible and kindly, but weak, old Emperor that the honour of Rome could not brook the undiplomatically blunt requests of the British kings. Probably all these influences were brought to bear upon Claudius, and induced him to undertake a conquest which in the end contributed materially to the weakening of Roman power. For the invasion Claudius concentrated four legions, with auxiliaries and cavalry, in Gaul. This meant 24,000 legionaries, supposing the cohorts to be at full strength, with, as is probable, as many auxiliaries. Taking the cavalry into consideration, and making a deduction of 20 per cent. for absentees, we can hardly reckon the force at less than 40,000 effectives; it may have been even stronger. The commander was Aulus Plautius, a veteran who had grown grey in war, and who, to judge from his record, was singularly fitted for his post. Claudius himself was on the way from Rome to join his army with the Prætorian Guard. For all practical purposes the Roman army was still the army of Marius and Cæsar, but the proportion of auxiliaries and cavalry was much greater. Of the legions three came from the Army of the Rhine: II., ‘Augusta’; XIV., ‘Gemina Martia’; and XX., ‘Valeria Victrix.’ From the Army of Pannonia, or the Upper Danube, came Legio IX., ‘Hispana.’ The XIVth was to win the proud title of ‘Conqueror of Britain’ during its stay of twenty-five years. ‘Valeria Victrix’ remained for more than three centuries, and the IInd did not leave until 407.