Henry IV of England, born Henry Bolingbroke, was king of England from 1399 to 1413 and the founder of the Lancastrian dynasty. He was the son of John of Gaunt ⓘ and Blanche of Lancaster.

During the reign of Richard II of England ⓘ Henry initially remained a loyal member of the royal aristocracy, but political tensions at court led to his exile in 1398. While Richard II was campaigning in Ireland in 1399 Henry returned to England and landed at Ravenspur in Yorkshire. What began as an attempt to recover his Lancastrian inheritance rapidly turned into a broader political revolt.

Support for Henry spread among the English nobility, and Richard’s government collapsed quickly. Several of the king’s principal councillors, including John Bussy ⓘ, Henry Green ⓘ, and William le Scrope ⓘ, were captured and executed. Richard II himself was taken into custody and compelled to abdicate the throne.

Henry was crowned king at Westminster in October 1399 as Henry IV. His reign was troubled by repeated rebellions, including the uprising of the Percy family and the revolt led by Owain Glyndŵr in Wales. Despite these challenges he succeeded in securing the Lancastrian succession, and was succeeded in 1413 by his son, Henry V of England.