Charles V (24 February 1500 – 21 September 1558) was Holy Roman Emperor from 1519, King of Spain (Castile and Aragon, as Charles I) from 1516, and ruling prince of the Habsburg Netherlands from 1506. Head of the rising House of Habsburg during the first half of the 16th century, his dominions in Europe included the Holy Roman Empire extending from
Germany to northern Italy with direct rule over Austria and the Low Countries, and a unified Spain with its southern Italian kingdoms of Naples, Sicily, and Sardinia. Furthermore, his reign encompassed both the long-lasting Spanish and short-lived German colonizations of the Americas. The personal union of the European and American territories of Charles V was the first collection of realms labelled "the empire on which the sun never sets".Born in Flanders to Philip the Handsome of the Austrian House of Habsburg (son of Maximilian I, Holy Roman Emperor and Mary of Burgundy) and Joanna the Mad of the Spanish House of Trastámara (daughter of Isabella of Castile and Ferdinand II of Aragon), Charles inherited all of his family dominions at a young age due to the premature death of his father and the mental illness of his mother. After the death of Philip in 1506, he inherited the Burgundian Netherlands originally held by his paternal grandmother. As a grandson of the Catholic Monarchs he was crowned King of Spain along with Joanna in 1516 and entered in control of the Castilian West Indies and the Aragonese Two Sicilies. Charles was the first king to rule Castile and Aragon simultaneously in his own right and as a result he is often referred to as the first king of Spain. At the death of his paternal grandfather in 1519, he inherited Austria and was elected to succeed him as Holy Roman Emperor. The personal domains of Charles remained mostly loyal to him except for four particularly dangerous rebellions quickly put down: the Revolt of the Comuneros in Castile, the Revolt of the Brotherhoods in Aragon, the revolt of the Arumer Zwarte Hoop in Frisia, and, later in his reign, the Revolt of Ghent.
Charles V revitalized the medieval concept of the universal monarchy of Charlemagne and spent most of his life defending the integrity of the Holy Roman Empire from the Protestant Reformation, the expansion of the Ottoman Empire and a series of wars with France. He made 40 journeys, travelling from country to country with no single fixed capital city, and it is estimated that he spent a quarter of his reign on the road. In order to finance the Imperial wars and maintain his armies of Spanish tercios, Italian condottieri, and German Landsknechte, Charles V relied on the economic productivity of the Habsburg Netherlands (birthplace of capitalism) and the flows of South American silver to Spain (his chief source of wealth). Charles ratified the Spanish conquest of the Aztec and Inca empires by the Spanish Conquistadores Hernan Cortes and Francisco Pizarro, the establishment of Klein-Venedig by the German Welser family in search of the legendary El Dorado, and the expedition of Ferdinand Magellan around the globe.
Crowned King in Germany and named defensor ecclesiae by Pope Leo X, Charles declared Martin Luther an outlaw at the Diet of Worms (1521) but he did not have him executed as Luther was put under the protection of Protestant princes. The same year Francis I of France, surrounded by the Habsburg possessions, started a conflict in Lombardy that lasted until the Battle of Pavia (1525) led to his temporary imprisonment. Two years later, the Protestant question re-emerged as Rome was sacked by mutinous Imperial soldiers of Lutheran faith. After ordering the retreat of the troops from the Papal States, Charles V defended Vienna from the Turks and obtained the coronation as King in Italy by Pope Clement VII at the Congress of Bologna. In 1535, he annexed the vacant Duchy of Milan and captured Tunis. Nevertheless, the Algiers expedition and the loss of Budapest in the early 40s frustrated his anti-Ottoman policies. Meanwhile, Charles V had come to an agreement with Pope Paul III for the organisation of the Council of Trent (1545). The refusal of the Lutheran Schmalkaldic League to take part in the Council led to a war, won by Charles V with the imprisonment of the Protestant princes. However, Henry II of France offered support to the Lutheran cause and forged a close alliance with the sultan Suleiman the Magnificent, the most dangerous enemy of Charles since 1520.
After four decades of incessant warfare and facing the prospect of an alliance between all of his enemies, Charles V conceded the Peace of Augsburg and abandoned his multi-national project with a series of abdications in 1556 that divided his hereditary and imperial domains between the Spanish Habsburgs headed by his son Philip II of Spain and the Austrian Habsburgs headed by his brother Ferdinand, who was Archduke of Austria under Charles' authority since 1521 and the designated successor as emperor since 1531. The Duchy of Milan and the Habsburg Netherlands were left in personal union to the King of Spain, but remained part of the Holy Roman Empire. The two countries remained allies until the extinction of the male line of the Spanish branch of the Habsburgs. In 1557, Charles retired to a monastery in Extremadura and there he died a year later. ...more on Wikipedia