Among the youths in the army whose beards had not yet grown, but who had just come of age, he [Alaric] chose out three hundred whom he knew to be of good birth and possessed of valour beyond their years, and told them secretly that he was about to make a present of them to certain of the patricians in Rome, pretending that they were slaves. And he instructed them that, as soon as they got inside the houses of those men, they should display much gentleness and moderation and serve them eagerly in whatever tasks should be laid upon them by their owners; and he further directed them that not long afterwards, on an appointed day at about midday, when all those who were to be their masters would most likely be already asleep after their meal, they should all come to the gate called Salarian and with a sudden rush kill the guards, who would have no previous knowledge of the plot, and open the gates as quickly as possible.cf. Edward Gibbon, The History of the Decline and Fall of the Roman Empire, Vol. IV (Oxford: D. A. Talboys, 1827), p. 130:
But they [the Romans] were unable to guard against the secret conspiracy of their slaves and domestics, who either from birth or interest were attached to the cause of the enemy. At the hour of midnight the Salarian gate was silently opened, and the inhabitants were awakened by the tremendous sound of the Gothic trumpet. Eleven hundred and sixty-three years after the foundation of Rome, the Imperial city, which had subdued and civilised so considerable a part of mankind, was delivered to the licentious fury of the tribes of Germany and Scythia.