The extant correspondence between Maximilian and Margaret, which is of the most confidential character, on matters of high policy, is a proof of the high opinion the emperor entertained of his daughter's intelligence and capacity. In nothing was his confidence more justified than in the assiduous care and interest that the regent took in the education of the Archduke Charles and his three sisters, who had been placed in her charge. In 1515 Charles, on entering his sixteenth year, was declared by Maximilian to be of age; Margaret accordingly handed over to him the reins of government and withdrew for the time into private life. Her retirement was not, however, to be of long continuance. On January 23, 1516, King Ferdinand of Aragon died, and Charles, who now became King of Castile and of Aragon, was obliged to leave the Netherlands to take possession of his Spanish dominions. Before sailing he reinstated his aunt as governess, and appointed a council to assist her. This post she continued to hold till the day of her death, for Charles was never again able to take up his permanent residence in the Netherlands. During the first years after his accession to the thrones of Ferdinand and Isabel he was much occupied with Spanish affairs; and the death of Maximilian, January 12, 1519, opened out to him a still wider field of ambition and activity. On June 28 Charles was elected emperor, a result which he owed in no small degree to the diplomatic skill and activity of Margaret. Just a year later the emperor visited the Netherlands, where Charles of Gelderland was again giving trouble, and his presence was required both for the purpose of dealing with the affairs of the provinces and also for securing a grant of supply, for he was sorely in need of funds. Margaret had at his request summoned the States-General to meet at Brussels, where Charles personally addressed them, and explained at some length the reasons which led him to ask his loyal and devoted Netherland subjects for their aid on his election to the imperial dignity. The States-General on this, as on other occasions, showed no niggardliness in responding to the request of a sovereign who, though almost always absent, appealed to their patriotism as a born Netherlander, who had been brought up in their midst and spoke their tongue. Charles was crowned at Aachen, October 23, 1520, and some three months later presided at the famous diet of Worms, where he met Martin Luther face to face. Before starting on his momentous journey he again appointed Margaret regent, and gave to her Council, which he nominated, large powers; the Council of Mechlin, the Court of Holland and other provincial tribunals being subjected to its superior authority and jurisdiction. By this action the privileges of the provinces were infringed, but Charles was resolute in carrying out the centralising policy of his ancestors, the Dukes of Burgundy, and he had the power to