John of Gaunt of Castile. As his father and elder brother, Edward, the Black Prince, became incapacitated due to 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 extremely unpopular figure for a time. John exercised great influence over the English throne during the minority of King Richard II, and the ensuing periods
John of Gaunt at Richard's behest. It may be that he felt he had to maintain this posture of loyalty to protect his son Henry Bolingbroke (the future Henry IV), who had also been one of the Lords Appellant, from Richard's wrath; but in 1398 Richard had Bolingbroke exiled, and on John of Gaunt's death the next year he disinherited Bolingbroke completely, seizing John's vast estates for the Crown. John of Gaunt was a patron and close friend of the poet Geoffrey Chaucer, most famously known for his work "The Canterbury Tales". Near the end of their lives, Lancaster and Chaucer became brothers-in-law.