JOHN II. (1609-1672), Casimir, king of Poland, second son of Sigismund III. and the duchess Constantia of Austria, was born March 21, 1609. After journeying in several countries of Europe, he in 1640 joined the Jesuit order at Rome, and shortly afterwards was chosen cardinal. Subsequently he returned to Poland, where he resided as a a layman until the death of his brother, 20th November 1648, when he succeeded him on the throne. In September 1668 he abdicated, after which he went to France, and became abbot of St Germains de Prés and of St Martin, at Nevers. He died September 16, 1672. For the events of his unfortunate reign see Poland.

JOHN II. (1455-1495), “the Perfect,” king of Portugal, succeeded his father, Alphonso V., in August 1481. His first business after ascending the throne was to curtail with a vigorous hand the overgrown power of his aristocracy; noteworthy incidents in the contest were the execution (in 1483) of the duke of Braganza for correspondence with Castile, and the murder, by the king’s own hand, of the youthful duke of Viseu for conspiracy. This reign was signalized by Bartolommeo Dias’s discovery of the Cape of Good Hope in 1486, and also by the equipment (1493) of a squadron for exploration of the new world recently discovered by Columbus. The latter proceeding led to disputes with Castile, until the claims of the disputants were adjusted by the famous treaty of Tordesillas (7th June 1494). John II. died, without leaving male issue, in October 1495, and was succeeded by his brother-in-law Emmanuel (Manoel) I.

JOHN II. (1397-1479), king of Aragon from 1458, was the younger son of Ferdinand I. (the Just), and was born June 29, 1397. He was twice married,—first to Blanche, daughter of Charles III. of Navarre, by whom he had three children (Carlos, heir to the crowns of Navarre and Aragon; Blanche, for some time the wife of Henry

IV. of Castile; and Eleanor, wife of Gaston, count of Foix); and afterwards (in 1447) to Joanna Henriquez, of the blood-royal of Castile, by whom he became the father of Ferdinand V. (the Catholic). For a long time he acted as lieutenant-general in Aragon for his brother Alphonso

V. , whom business detained in his Neapolitan dominions; in this capacity he intervened frequently in the affairs of Castile, where his weak and inexperienced kinsman John II. occupied the throne, and on one occasion (1444) he invaded that kingdom, but was defeated at Olmedo. On his second marriage he irritated his son Carlos and the community by sending his queen Joanna to share the administration of Navarre with his son; in the revolt which ensued victory declared for John, Carlos himself being reduced to captivity (1452), in which he was detained for many months. In May 1458 John succeeded his brother in Aragon, Sicily, and Sardinia; but the influence of Joanna Henriquez prevented him from recognizing the legitimate claims of his own eldest son to the reversion; an attempt by Carlos to obtain support in other quarters led to his arrest and imprisonment, from which he was released only after Catalonia had risen in arms and the king of Castile had begun an irruption into Navarre. Shortly after this temporary triumph Carlos was carried off by a fever in September 1461, bequeathing the crown of Navarre to his sister Blanche and her posterity. Ferdinand, the half-brother of Carlos, was now put forward as heir apparent of the Aragonese throne, but the indignant Catalonians raised a revolt which did not come to an end until December 1472. Immediately afterwards John entered upon a war with Louis XI. of France in consequence of disputes about Roussillon and Cerdagne; first successful, but afterwards worsted, this bold and energetic but ambitious and unjust prince died January 20, 1479, before the conclusion of the peace. He was succeeded by Ferdinand V.

JOHN II. (1404-1454) of Castile and Leon, grandson of the preceding, succeeded to the throne when only twenty-two months old. Until 1412 the regency was shared with his mother Catherine by his uncle Ferdinand (afterwards Ferdinand IV. of Aragon); this period was marked by much internal prosperity and by important conquests from the Moors, especially by the capture of Antequera. Unfortunately for Castile, Ferdinand was called away (in 1412) to occupy the throne of Aragon; but it was not until after the death of Catherine in 1418 that John’s weakness and incapacity came to be fully seen. Abandoning himself recklessly to a life of frivolous pleasure, he left the affairs of his kingdom in the hands of a few favourites, such as the archbishop of Toledo and Juan de Velasco. From 1423 onwards he was the tool principally of Alvaro de Luna, a brilliant, ambitious, and crafty courtier. Henceforward the history of his reign is largely a record of the internal commotions, rising sometimes to the height of civil war, occasioned by the nobles’ jealousy of Alvaro, and by the oppressions to which the common people were exposed under the absolutist policy of that minister. The period of John II. is chiefly and most favourably remembered in connexion with the history of Castilian literature: a man of some literary turn himself, he was a liberal patron of letters; and his countenance gave an impulse to refinement and culture of literary style, the effects of which were distinctly traceable through several subsequent generations. By his first wife John II. became the father of Henry IV., his successor; the daughter of a second marriage was Isabella, afterwards known as “the Catholic.” He died in June 1454.

JOHN III. (1502-1557) of Portugal was born at Lisbon, June 6, 1502, and ascended the throne as successor of his father Emmanuel L in December 1521. In 1524 he married Catherine, sister to the emperor Charles V., who in turn shortly afterwards married the infanta Isabella, John’s sister. Succeeding to the crown at a time when Portugal was at the height of its political power, and Lisbon in a position of commercial importance previously unknown, John III., unfortunately for his dominions, yielded so far to the counsels of the clerical party among his subjects as to consent to the introduction of the Inquisition (about 1526); this led to measures of tyranny and oppression which, notwithstanding the enactment of many wise laws, soon avenged themselves in disastrous consequences to the commercial and social prosperity of his kingdom. The conflicts in which Portugal engaged with the Moors and the Turks during his reign were comparatively unfruitful of results. He died of apoplexy on June 6, 1557, and was succeeded by his grandson Sebastian, then a child of only three years.