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 enforce his will in spite of the protests that were raised.  And so under the wise and conciliatory but firm administration of Margaret during a decade of almost continuous religious and international strife—­a decade marked by such great events as the rapid growth of the Reformation in Germany, the defeat and capture of Francis I at Pavia, the sack of Rome by the troops of Bourbon and the victorious advance of the Turks in Hungary and along the eastern frontier of the empire—­the Netherland provinces remained at peace, save for the restless intrigues of Charles of Egmont in Gelderland, and prospered.  Their wealth furnished indeed no small portion of the funds which enabled Charles