Returning to England in April 1381, Thomas of Woodstock found that his brother,
John of Gaunt, had arranged a marriage between Thomas's sister-in-law,
Mary de Bohun, and John's own son
Henry Bolingbroke. The relations between the brothers, hitherto somewhat strained, were not improved by this event; presumably, Thomas was hoping to retain possession of Mary's estates. Still, having taken part in crushing the
Peasants' Revolt in 1381, Thomas became more friendly with John, and in 1385 was created Duke of Gloucester. However, this mark of favour did not prevent him from taking up an attitude of hostility to his nephew,
Richard II. Thomas placed himself at the head of the party that was opposed to the royal advisers,
Michael de la Pole, 1st Earl of Suffolk, and
Robert de Vere, Earl of Oxford, whose recent elevation to
Duke of Ireland had aroused discontent. Supported by those who were indignant at the extravagance and incompetence, real or alleged, of the king, Thomas was soon in a position of authority. He forced the dismissal and impeachment of Suffolk; was a member of the
commission appointed in 1386 to reform the kingdom and the royal household; and took up arms when Richard began proceedings against the commissioners. Having defeated de Vere at the
Battle of Radcot Bridge in December 1387 the duke and his associates entered London to find the king powerless in their hands. Thomas, who had previously threatened his nephew with deposition, was only restrained from taking this extreme step by the influence of his colleagues; but, as the leader of the "
Lords Appellant" in the "
Merciless Parliament," which met in February 1388 and was packed with his supporters, he took revenge upon his enemies, which culminated in a successful rebellion in 1388 that significantly weakened the king's power. Richard II quickly regained control and eventually, in 1397, managed to dispose of the Lords Appellant. By 1396, Thomas and Richard were again at odds over policy. In 1397, Thomas was arrested at his home by the king himself and was imprisoned in Calais to await trial for treason. On 9 September 1397, he was murdered by being smothered between two feather beds, probably by a group of men led by
Thomas de Mowbray, 1st Duke of Norfolk, and the knight Sir
Nicholas Colfox, presumably on behalf of Richard II; parliament declared him guilty of treason and his estates forfeited. These events caused an outcry among the nobility of England that is considered by many to have added to Richard's unpopularity. Thomas was buried in
Westminster Abbey, first in the Chapel of Saint Edmund and Saint Thomas in October 1397, and two years later reburied in the
Chapel of Saint Edward the Confessor. His wife was buried next to him. ==Marriage and progeny==