Maximilian I (22 March 1459 – 12 January 1519), the son of Frederick III, Holy Roman Emperor and Eleanor of Portugal, was King of the Romans (also known as King of the Germans) from 1486 and Holy Roman Emperor from 1508 until his death, though he was never in fact crowned by the Pope, the journey to Rome always being too risky. He had ruled jointly with his father for the last ten years of his father's reign, from c. 1483. He expanded the influence of the House of Habsburg through war and his marriage in 1477 to Mary of Burgundy, the heiress to the Duchy of Burgundy, but he also lost the Austrian territories in today's Switzerland to the Swiss Confederacy.
By marrying his son Philip the Handsome to the future Queen Joanna of Castile in 1498, Maximilian established the Habsburg dynasty in Spain and allowed his grandson Charles to hold the throne of both León-Castile and Aragon, thus making him the first de jure King of Spain. Since his father Philip had died in 1506, Charles succeeded Maximilian as Holy Roman Emperor in 1519, and thus ruled both the Holy Roman Empire and the Spanish Empire simultaneously.
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