Charles V 
emperor of Germany and king of Spain (under the title of Don Carlos I), eldest son of Philip, archduke of Austria, and Joanna, second daughter of Ferdinand and Isabella of Spain, was born at Ghent, Feb. 24th, 1500, and died at the monastery of San Yuste, near Placencia, in Estramadura, Spain, Sept. 21st, 1558. His father died when he was only six years of age, and his grandfather Maximilian became his guardian, and placed him under the care of William de Croy, lord of Chi È vres, as governor, and Adrian of Utrecht, afterwards Pope Adrian VI, as preceptor. On the death of his grandfather Ferdinand, Charles, conjointly with his mother, was acknowledged as his successor, and visited Spain in 1517, where the conduct of his Flemish ministers gave rise to serious troubles. In the year 1519 his grandfather Maximilian died, and Charles became a competitor for the imperial crown. Through the efforts of Frederick the Wise, elector of Saxony and regent of the empire, he was chosen over Francis I of France, his principal rival, June 28th, 1519. This contest ripened the jealousy between these young and ambitious sovereigns into an enmity which gave rise to four wars, and ended only with the death of Francis. Charles was crowned emperor with great pomp at Aix-la- Chapelle, Oct. 22, 1520. His first act was to issue a call for convoking a diet at Worms early the next year, especially to consider the means of suppressing the new religious ideas awakened by the teachings of Luther. This assembly was held April 17-26, 1521, and thither Luther repaired under a safe-conduct, and plead his cause; but an edict of outlawry was pronounced against him. (See Worms).
The prudent action of his patron, Frederick of Saxony, in having him taken to the Wartburg, and the almost sovereign power of the German princes, saved the reformer and his cause from the impending danger; while the wars with France, 1521-6 and 1527- 9 forced Charles to "leave the conduct of German affairs to the established authorities, who were not opposed to a reform of the Church, and who, instead of executing the edict of Worms, persisted in the demand for a general council 'to be held in a German city.' " At the Diet of Spires, 1526, a decree was signed by Charles's brother, Ferdinand, as his representative, which left to each state of Germany the right to regulate its religious affairs, which decree, according to Ranke, was the basis of the legal existence of Protestantism in Germany. At a second diet at Spires, in March, 1529, the Roman Catholic party, emboldened by the more favorable aspect of Charles's affairs abroad, sought to prevent the farther progress of the Reformation by a decree "that the Church should remain in statu quo until the convocation of a council." This led to the celebrated Protest of the Lutheran princes, April 19, 1529, from which the name Protestant arose. This protest was not favorably received by Charles; but the fear of the Turks, who had laid siege to Vienna, compelled moderation on his part until their retreat, when the subject again came up at the Diet of Augsburg (1530). In accordance with the promise of Charles that each party should lay before this diet a statement in Latin and German of their opinions, the Reformers presented the Augsburg Confession (q.v.), drawn up by Melancthon, which was read June 25th, and produced so powerful an impression that many Roman Catholic princes inclined to a milder judgment of the new faith.
No statement was presented by the other party, but the emperor caused a refutation of the Lutheran Confession to be prepared, to which the Protestants replied in the Apologia Confessonis, also from the pen of Melancthon; but this failed to change the purpose of Charles, who, influenced by Campeggio, the papal legate, issued a decree, Nov. 19, 1530, condemning the Confession, and requiring its adherents to submit unconditionally, until a future general council, and to be reconciled to the Roman Catholic Church within seven months. The design of the emperor to force submission to his will in matters of religion was now evident, and, to protect themselves, the Protestant princes and states formed the "League of Smalcald," Feb. 27, 1531, and made treaties with France, England, and Denmark. Confronted by so formidable a coalition, and threatened with a new invasion of Austria by the Turks under Solyman, Charles was forced to grant the "Truce of Nuremberg," July 23, 1532, by which liberty of conscience was allowed until the assembling of a council.
The constant pressure of foreign enterprises, and the necessity of conciliation within the empire, to ward off outward dangers, postponed for some years the armed conflict between Charles and his Protestant subjects; and at the Diet of Spires, 1544, considerable concessions were made to them in order to secure their hearty support against the French. But when the war was ended, the Protestants saw plainly that Charles purposed to compel their submission to the decrees of the Council of Trent, then assembled by Paul III, and they prepared to defend their religious liberties by arms. Owing to the lack of energy and decision on the part of their leaders, and the skill of Maurice of Saxony, who took the side of Charles, they failed of success, and were totally defeated at M Ü hlberg.
Shortly before this, the death of Francis and Henry VIII had freed Charles from his most powerful external foes, and he might now hope, aided by the pope and the new order of the Jesuits, to compel religious unity in Germany. Accordingly, he convoked a diet at Augsburg with this view; but after he had with great difficulty induced the Protestants to accept conditionally the Council of Trent, the pope removed the council to Bologna, and would neither change the place nor make any concessions to the Protestants. This so irritated Charles that he caused a declaration to be drawn up by Pflug, Helding, and Agricola, called the Interim (q.v.), to serve as a rule of faith and practice until a free and general council — a plan which pleased neither party. But Charles was now too powerful for open resistance. Maurice of Saxony, however, began to form schemes for humbling him, and so well did he conceal his purposes, that he was even appointed to the command of the army intended to compel the refractory city of Magdeburg to receive the Interim. Having formed alliances with France and other powers, and provided for the support of his army, Maurice openly declared against Charles in March, 1552, and by his rapid and successful movements extorted from the emperor the treaty of Passau, Aug. 2, 1552, by which, together with the release of the captive princes, complete religious liberty was granted to the Protestants — terms subsequently confirmed by the Recess or Religious Peace of Augsburg, Sept. 21,1555.
The star of Charles had now passed its zenith. The consuming cares of a life devoted to exciting and ambitious schemes, and the uncontrolled indulgence of an excessive appetite, not to say gluttony, had left their impress in failing powers and tormenting disease; and now that he saw his cherished hope of universal monarchy and an imperial throne for his son fading away, baffled and disappointed by Fortune, which n e, peevishly described as a woman who smiled on his youth, but forsook him in his age, he determined to throw off the prerogatives and responsibilities of power, and seek in retirement ease of mind and body. Accordingly, Oct. 25th, 1555, before an assembly of the estates of the Netherlands, convened at Brussels for that purpose, he resigned the crown of those provinces, and, Jan. 15,1556, at the same place, in the presence of the grandees of Spain, the crown of Spain to his son Philip II; and on August 27, 1556, also the imperial crown, in favor of his brother Ferdinand. He set out, Sept. 17th, 1556, for his chosen retreat, the Hieronymite monastery of San Yuste, where, by his orders, separate buildings had been erected for himself and the few servants who accompanied him. Here he remained until his death, occupied in religious exercises, gardening, and mechanical experiments, without, as recent researches show, losing sight of the political and religious movements of the outer world.
He is described as possessing dignity and elegance of manner, slow in resolving, but prompt to execute, patient of every hardship but hunger, firm and self-possessed in danger, but without the warmth of genius or that noble directness of character which subordidnates selfish aims to the higher claims of humanity and right. Though amiable in private life, his inhuman persecution of his Protestant subjects in the Netherlands, and his testamentary directions to his son, evince the feelings of a bigot and a tyrant; while his course towards the Reformation in Germany proves how readily his secret preferences were made to yield to the promptings of policy, when the furtherance of his ambitious plans demanded a show of moderation in dealing with the newly-awakened desire of the age for religious reform. — Herzog, Real-Encyklop Ä die, 7:379 sq.; Hoefer, Nouv. Biog. Generale, 9:269; Heine, Briefe an Karl V, geschrieben von s. Beichtvater (Berlin, 1848, 8vo); Sleidan, De statu religionis, etc. Carolo V Caesare commentarii (Frankf. 1785, 3 vols: 8vo); Ranke, History of the Reformation; Prescott, History of Philip II; Ranke, History of the Papacy (2 vols. 8vo, 1851); Motley, The Rise of the Dutch Republic (3 vols. 8vo, N. Y. 1857); Sismondi, Histoire des Frangais, 18 vols. 8vo (Bruxelles, 1849; see index in 18th vol.); Robertson, History of the Reign of Charles V; Lanz, Correspondenz des Kaisers Karl V (Leipz. 1844-46, 3 vols.); Kervyn de Lettenhove, Aufzeichnungen des Kaisers Karl V (German transl. Leipz. 1862); Gachard, Correspond. de Charles Quint (Brussels, 1859). Special works on the life of Charles V after his abdication and retirement have been written by Stirling (Cloister Life of the Emperor Charles the Fifth, N. Y. 12mo), Gachard (Retrait et Mort de Ch. V (Brussels, 1854-55), Pichot (Chronique de Charles V, Paris, 1854), and Migne (Charles Quint, Paris, 1854).