Carlos, who is better known to history as the Holy Roman Emperor Charles V, is one of the most important figures in European history, a pivotal figure. He was a eligible for the office of Holy Roman Emperor because his grandfather had been the HRE. His grandmother, Mary of Burgundy, brought with her the Duchy of Burgundy, and therefore made him heir to the Low Countries, what we would think of as Holland, Belgium, Luxembourg and a wide swath of western Germany, as well as portions of northern France--France as we know it. He convened the Imperial Diet (the Diet of Worms) over which he presided and at which he hoped to arrest Martin Luther. He also subsequently waged the wars of the Reformation, attempting to extirpate Protestantism. He married his son Philip off to Mary of England. That lead Philip to decide that he had the right to the English throne, which was why he insisted that Elizabeth marry him, and launched the Armada--which was a more complex operation that one would know from reading English history.
In 1555, Charles, King Carlos, abdicated in favor of his son Philip, named for his father. (He abdicated various positions and titles piecemeal from 1554 to 1556.) However, the German electors were not going to elect some lunatic from Spain as the next HRE, no matter how many bribes were promised. Charles retired to a monastery and died three years later, although he continued to dominate his son and to correspond widely with supporters of the counter-Reformation throughout Europe. His legacy continued after his death.
Because he had inherited the Netherlands, after his death, his son Philip ruled there. To celebrate the event, they had a little friendly was with France, fighting over the city of St. Quentin. The French won, and the King, Henri, invited the "Spaniards" (we would thing Belgians and Dutch) to Paris for a big party. One of the "Spanish" heroes was William, the Count of Nassau (born in Germany, we would consider his a Dutchman). To honor him, the French king resurrected the principality of Orange in south central France, and conferred it on William, whose mother was descended from the then extinct princely family. So, he became the Prince of Orange, although he never really enjoyed his heritage. While in Paris, King Henri invited him to go hunting, and then blabbed about the plan that he and Philip had to slaughter Protestants in their respective realms. William said nothing, earning him the sobriquet of Guillaume le taciturne
, William the Silent. William warned people when he got back home, and the plan was undone. It would be seven more years before the French moved against Protestants in France, and a rebellion began to fester in the Low Countries.
Philip put the rule of the Netherlands nominally under his bastard sister the Duchess of Parma, and Brussels filled up with arrogant Spanish grandees who sneered at the local nobility and lorded it over the locals, attempting to rule with a heavy hand. Philippe III of Burgundy had established the Order of he Golden Fleece, the most prestigious international order in Europe, and Charles V had, by his inheritance from Mary of Burgundy, become the leader of the Order. The Spanish grandees in Brussels included some members of this order, and they had sneered at the local nobility, and called them beggars. So they established a rival, satirical order, wo wore expensive gold chains like that used in the Order of the Golden Fleece, but with a wallet, begging bowl and foot stool suspended from the chain (the symbols of a beggar), rather than a fleece--it was mockery of Philip, and many of the Spaniards considered it to be lèse-majesté
, then a capital offense. These tension and others escalated and eventually lead to the Eighty years war, which the Dutch fought to secure their independence. The rest of he Low Countries nominally remained a part of Spain, but were eventually handed over to Austria in 1714, after the War of the Spanish Succession. The Spanish Armada's principle mission was not to threaten England, but to deliver troops and artillery to the Low Countries to fight the seemingly endless rebellion. (The English have a habit common to all of mankind, of thinking themselves and their affairs to be at the center of the universe.)
The legacy of King Carlos, of the Emperor Charles V, spread widely throughout Europe, and lasted well after his death.