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 agree to the imposition of the first Poll Tax in English history – a viciously regressive measure that bore hardest on the poorest members of society. There was organised opposition to his measures and rioting in London; John of Gaunt's arms were reversed or defaced wherever they were displayed, and protestors pasted up lampoons on his supposedly dubious birth. At one point he was forced to take refuge across the Thames, while his Savoy Palace only just escaped looting. It was rumoured (and believed by many people in England and France) that he intended to seize the throne for himself