ohn of Gaunt (1340-99), Duke of Lancaster, the fourth son of Edward III, was born in Ghent. After the close of the Black Prince’s expedition to help Pedro the Cruel of Castile, John married Constance, daughter of Pedro, and in 1372 assumed the title of King of Castile. In England, where he exercised great influence, he supported Wycliffe, but failed to gain the confidence of the House of Commons. His eldest son, Henry Bolingbroke, became king as Henry IV. [World Wide Illustrated Encyclopedia, 1935]

Notes on John of Gaunt, Duke of Lancaster
The fourth son of Edward III, he was born at Ghent. In 1359 he married his cousin, Blanche of Lancaster, and was created Duke in 1362. She died in 1369, and in 1372 he married Constance, daughter of Pedro the Cruel of Castile, and assumed the title of king of Castile, though he failed by to oust his rival, Henry of Trastamare. Before his father’s death, John became the most influential personage in England, and was thought to be aiming at the crown. He opposed the clergy and protected Wycliffe (the first translator of the complete Bible into English). Young King Richard, distrusting him, sent him in 1386 on another attempt to secure the crown of Castile; and this time he secured a treaty for the marriage of his daughter, Catharine, to the future King of Castile. After his return to England in 1389, he reconciled Richard to his (John’s) brother, the Duke of Gloucester, and by Richard was made Duke of Aquitaine, and sent on several embassies to France. On his second wife’s death, he had married in 1396 his mistress, Catharine Swynford, by whom he had three sons, legitimated in 1397; from the eldest descended Henry VIII. {Chamber’s Biographical Dictionary} [GADD.GED]

John of Gaunt, Duke of Lancaster (1340-99), English soldier and statesman, the fourth son of King Edward III of England, and brother of Edward, the Black Prince. John was born in March 1340 in Ghent (M.E., Gaunt), now in Belgium. In 1359 he married Blanche, daughter of Henry, duke of Lancaster; when Henry died, John became duke.

John of Gaunt played an important part in the wars of the period between England and France and between England and Spain. He commanded a division of the English army, led by the Black Prince, that defeated the army of Henry (later Henry II, king of Castile and León) at Nájera in 1367. As a result of his second marriage, to Constance, daughter of Peter the Cruel (king of Castile and León), John laid claim to the throne of Castile. During the Hundred Years' War, he aided (1370-71) the Black Prince against France and established English rule over most of southern France. After a severe illness forced the return of the Black Prince to England, John took command of the English armies; by 1380 he had lost much of the territory the English had previously won. In 1386 John invaded Castile, but was defeated by John I, king of Castile and León. John of Gaunt gave up his claim to Castile and León in 1387, when his daughter married Henry, later Henry III, king of Castile and León.

John of Gaunt was also prominent in English affairs. Together with Alice Perrers, his father's mistress, John dominated the English government. He was opposed by Parliament and by the Black Prince. In 1376 Parliament banished Alice Perrers and curtailed John's powers. The death of the Black Prince that year and the dissolution of Parliament, however, enabled John to regain his power. In 1377, on the death of Edward III and the accession of Richard II (John's nephew and son of the Black Prince), John gave up his control of the government and thereafter played the role of peacemaker; he also supported the king, by whom he was made (1390) duke of Aquitaine. In 1396, after the death of his second wife, John married his mistress Catherine Swynford, and Richard legitimized their children the following year. Saddened by the exile (1398) of his son, Henry of Lancaster (later King Henry IV of England), John died on February 3 of the following year. [Microsoft Encarta 98 Encyclopedia]

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