The new king was immediately faced with insurrections. Early in 1400, supporters of Richard II rebelled, but the revolt was easily suppressed and most of its leaders were subsequently executed. Richard himself died at Pontefract Castle, either by self-starvation or murdered on Henry's orders. The Welsh, aided by France, also revolted in 1400, and Henry led an ineffective invasion of Scotland. The Scots were decisively defeated in 1402 at Homildon Hill, but the Welsh continued their rebellion under Owen Glendower. The Percys (Sir Henry Percy, his father, the 1st earl of Northumberland, and his uncle, the earl of Worcester), once the king's partisans, unexpectedly rebelled and were defeated at Shrewsbury in 1403. A rebellion of 1405 in the north was crushed, and the leaders, among them Richard Le Scrope, archbishop of York, were executed; Henry was severely criticized for their deaths. Despite the capture (1406) of James (later James I), heir to the Scottish throne, trouble with Scotland continued under Robert Stuart, 1st duke of Albany. Northumberland's new rebellion was put down at Bramham Moor in 1408, the Welsh were crushed shortly afterward (though Owen Glendower was not captured), and the French armies ceased to harry English possessions in France.
No sooner had his military troubles ended than others began for Henry—an illness that left him an invalid for much of his few remaining years and a somewhat obscure struggle between two parties, one of them led by his son, the future Henry V, for control of the council. Henry V came to a throne made temporarily secure by the military efforts of his father, but Henry IV had lacked the skill and patience to restore the financial stability of the crown, now enormously in debt, and to provide a satisfactory administration of civil justice.