It has been alleged that the Roman armies were neither so robust nor so well disciplined in the fifth century as they had been in an earlier age. However this may be, they could still give a good account of themselves when matched on equal terms with the most warlike of the barbarians. It was in patriotism and in numbers, rather than in professional efficiency, that they failed when put to the supreme test. The armies were now largely recruited with barbarians, who numbered more than half the fighting strength and were esteemed the flower of the Roman soldiery. Many of these hirelings showed an open contempt for their employers, and sympathised with the enemies whom they were paid to fight. Furthermore, each army, whatever its constituent elements, tended to be a hereditary caste, with a strong corporate spirit, respecting no authority but that of the general. The soldiers had no civic interests; but they had standing grievances against the Empire. Any political crisis suggested to them the idea of a mutiny led by the general, sometimes to obtain arrears of pay and donatives, sometimes to put their nominee upon the throne. The evil was an old one, dating from the latter days of the Republic, when Marius, in the interests of efficiency, had made military service a profession. But it was aggravated under the successors of Diocletian, as the barbarian element in the armies increased and the Roman element diminished. Its worst effects appeared in the years 406-407. The German inroads upon Italy and Gaul were then followed by the proclamation of military usurpers in Britain and on the Rhine; the Roman West was divided by civil war at the very moment when union was supremely important. Hence the strange spectacle of the Visigoths, still laden with the spoils of Rome, entering Gaul by invitation of the Empire to fight against imperial armies.