When fifteen years of age, the prince was taken into the imperial household, and became the page of Charles the Fifth. The emperor was not slow in discerning the extraordinary qualities of the youth; and he showed it by intrusting him, as he grew older, with various important commissions. He was accompanied by the prince on his military expeditions, and Charles gave a remarkable proof of his confidence in his capacity, by raising him, at the age of twenty-two, over the heads of veteran officers, and giving him the command of the imperial forces engaged in the siege of Marienburg. During the six months that William was in command, they were still occupied with this siege, and with the construction of a fortress for the protection of Flanders. There was little room for military display. But the troops were in want of food and of money, and their young commander's conduct under these embarrassments was such as to vindicate the wisdom of his appointment. Charles afterwards employed him on several diplomatic missions,--a more congenial field for the exercise of his talents, which appear to have been better suited to civil than to military affairs. The emperor's regard for the prince seems to have increased with his years, and he gave public proof of it, in the last hour of his reign, by leaning on William's shoulder at the time of his abdication, when he made his parting address to the states of the Netherlands. He showed this still further by selecting him for the honorable mission of bearing the imperial crown to Ferdinand. On his abdication, Charles earnestly commended William to his successor. Philip profited by his services in the beginning of his reign, when the prince of Orange, who had followed him in the French war, was made one of the four plenipotentiaries for negotiating the treaty of Cateau-Cambresis, for the execution of which he remained as one of the hostages in France. While at the court of Henry the Second, it will be remembered, the prince became acquainted with the secret designs of the French and Spanish monarchs against the Protestants in their dominions; and he resolved, from that hour, to devote all his strength to expel the "Spanish vermin" from the Netherlands. One must not infer from this, however, that William, at this early period, meditated the design of shaking off the rule of Spain altogether. The object he had in view went no further than to relieve the country from the odious presence of the Spanish troops, and to place the administration in those hands to which it rightfully belonged. They, however, who set a revolution in motion have not always the power to stop it. If they can succeed in giving it a direction, they will probably be carried forward by it beyond their intended limits, until, gathering confidence with success, they aim at an end far higher than that which they had originally proposed. Such, doubtless, was the case with William of Orange.