1500-1558. Holy Roman Emperor, king of Spain. The grandson of Maximilian of Habsburg, Mary of Burgundy, Ferdinand of Aragon, and , he fell heir to an empire greater than Charlemagne's. Born and reared in Flanders, he inherited the Netherlands and Franche-Comté (1506), and Spain, Naples, Sicily, and the American possessions (1516). Although initially resented by his Spanish subjects, he earned their loyalty by identifying with their national traits, by his religious zeal, and by marriage to a Portuguese princess. Maximilian's death in 1519 brought him the Habsburg duchies in Austria and Germany, together with rights over Bohemia and Hungary. He also obtained the imperial throne through bribery and granting significant concessions to the estates. The medieval ideal of unifying all Christendom under one scepter, however, was a hopeless anachronism. He was a man of perseverance, patience, and intelligence, but the obstacles facing him were insuperable. His empire had no common ties, while three great problems plagued his reign-the religious revolt in Germany, the Turkish threat, and the continuing struggle with France for European hegemony.
Although strongly opposed to Lutheranism, Charles was absent from the empire during the crucial 1520s. His brother Ferdinand, appointed regent over the German lands in 1521-22, was preoccupied with the Turkish menace. Charles gained the upper hand over Francis I of France in two Italian wars (his army sacked Rome in 1527) and was the last emperor to be crowned by the pope (1530). Unable to crush Lutheranism at the Diet of Augsburg (1530), faced by a defensive coalition (*), and needing help against the Turks, Charles made a truce with Protestant princes (Nuremberg Standstill, 1532). While he campaigned in against Barbary pirates and vassals of the Sultan (1535, 1541) and fought with Francis (1536-38, 1542- 44), Protestantism spread rapidly in Germany. But when divisions appeared in the movement, Charles attacked and defeated the Smalcald League in 1546-47. The defeat, along with his unpopular theological settlement (Augsburg Interim, 1548), forced the Protestants into an alliance with Henry II of France in 1552, and into a new round of conflict. Finally recognizing that Lutheranism could not be destroyed, Charles authorized Ferdinand to conclude a religious peace at Augsburg in 1555. Tired and discouraged, Charles divided his possessions between his son Philip (Spain, the Netherlands, and Sicily) and Ferdinand (Habsburg hereditary lands), while retaining the imperial title. His last two years were spent in retirement at the monastery San Yuste in Estremadura, Spain.
K. Brandi, The Emperor Charles V (1939); H. Holborn, History of Modern Germany, vol. 1 (1959); W. Robertson and W.H. Prescott, The History of the Reign of the Emperor Charles V (3 vols., 1902); G. von Schwarzenfeld, Charles V: Father of Europe (1957).