John of Gaunt

John of Gaunt, Duke of Lancaster (6 March 1340 – 3 February 1399), was an English prince, military leader and statesman. He was the fourth son (third surviving) of King Edward III, and the father of King Henry IV. Because of Gaunt's royal origin, advantageous marriages and some generous land grants, he was one of the richest men of his era and an influential figure during the reigns of both his father and his nephew, Richard II. As Duke of Lancaster, he was the founder of the royal House of Lancaster, whose members ascended the throne after his death. His birthplace, Ghent in Flanders, then known in English as Gaunt, was the origin of his name.

John's early career was spent in France and Spain fighting in the Hundred Years' War. He made an abortive attempt to enforce a claim to the Crown of Castile that came through his second wife, Constance of Castile, and for a time styled himself as King of Castile. When Edward the Black Prince, Gaunt's elder brother and heir apparent to the ageing Edward III, became incapacitated by poor health, Gaunt assumed control of many government functions and rose to become one of the most powerful political figures in England. He was faced with military difficulties abroad and political divisions at home, and disagreements as to how to deal with these crises led to tensions between Gaunt, the English Parliament and the ruling class, making him an unpopular figure for a time. He helped forge the 1386 Anglo-Portuguese alliance, secured through the marriage of his daughter Philippa to John I of Portugal, which is still in force today.

John exercised great influence over the English throne during the minority of King Richard II (Edward the Black Prince's son) and the ensuing periods of political strife. He mediated between the king and a group of rebellious nobles, which included Gaunt's own son and heir-apparent, Henry Bolingbroke. Following Gaunt's death in 1399, the Lancastrian estates and titles were declared forfeit to the Crown, and the now disinherited son, Bolingbroke, was branded a traitor and ordered into exile. Henry did not stay in exile; he raised an army to reclaim his inheritance and depose Richard. He reigned as King Henry IV (1399–1413), the first of the descendants of John of Gaunt to hold the English throne.