In spite of the favour that Henry IV showed the Percys in many respects, they became increasingly discontented with him.
Among their grievances were:
The king's failure to pay the wages due to them for defending the Scottish border
The king's favour towards Dunbar
The king's demand that the Percys hand over their Scottish prisoners
The king's failure to put an end to Owain Glyndŵr's rebellion through a negotiated settlement
The king's increasing promotion of his son's (Prince Henry) military authority in Wales
The king's failure to ransom Henry Percy's brother-in-law, Sir Edmund Mortimer, whom the Welsh had captured in June 1402
Spurred on by these grievances, the Percys rebelled in the summer of 1403 and took up arms against the king.
According to J. M. W. Bean, it is clear that the Percys were in collusion with Glyndŵr.
On his return to England shortly after the victory at Homildon Hill, Henry Percy issued proclamations in Cheshire accusing the king of 'tyrannical government'.

Joined by his uncle, Thomas Percy, Earl of Worcester, Percy marched to Shrewsbury, where he intended to do battle against a force there under the command of the Prince of Wales.
The army of his father, however, was slow to move south and it was without the assistance of his father that Henry Percy and Worcester arrived at Shrewsbury on 21 July 1403, where they encountered the king with a large army.
The ensuing Battle of Shrewsbury was fierce, with heavy casualties on both sides but, when Henry Percy himself was struck down and killed, his own forces fled.

The circumstances of Percy's death differ in accounts.
The chronicler Thomas Walsingham stated, in his Historia Anglicana that "while he led his men in the fight rashly penetrating the enemy host, [Hotspur] was unexpectedly cut down, by whose hand is not known".
Another account states that Percy was struck in the face by an arrow when he opened his vizor for a better view.
The legend that he was killed by the Prince of Wales seems to have been given currency by William Shakespeare, writing at the end of the following century.

The Earl of Worcester was executed two days later.

King Henry, upon being brought Percy's body after the battle, is said to have wept.
The body was taken by Thomas Neville, 5th Baron Furnivall to Whitchurch, Shropshire for burial.
However, when rumours circulated that Percy was still alive, the king "had the corpse exhumed and displayed it, propped upright between two millstones, in the market place at Shrewsbury".
That done, the king dispatched Percy's head to York, where it was impaled on the Micklegate Bar (one of the city's gates).
His four-quarters were sent to London, Newcastle upon Tyne, Bristol, and Chester before they were finally delivered to his widow.
She had the body buried in York Minster in November of that year.
In January 1404, Percy was posthumously declared a traitor, and his lands were forfeited to the Crown.
In spite of the favour that Henry IV showed the Percys in many respects, they became increasingly discontented with him. Among their grievances were:
The king's failure to pay the wages due to them for defending the Scottish border
The king's favour towards Dunbar
The king's demand that the Percys hand over their Scottish prisoners
The king's failure to put an end to Owain Glyndŵr's rebellion through a negotiated settlement
The king's increasing promotion of his son's (Prince Henry) military authority in Wales
The king's failure to ransom Henry Percy's brother-in-law, Sir Edmund Mortimer, whom the Welsh had captured in June 1402
Spurred on by these grievances, the Percys rebelled in the summer of 1403 and took up arms against the king. According to J. M. W. Bean, it is clear that the Percys were in collusion with Glyndŵr. On his return to England shortly after the victory at Homildon Hill, Henry Percy issued proclamations in Cheshire accusing the king of 'tyrannical government'.
Joined by his uncle, Thomas Percy, Earl of Worcester, Percy marched to Shrewsbury, where he intended to do battle against a force there under the command of the Prince of Wales. The army of his father, however, was slow to move south and it was without the assistance of his father that Henry Percy and Worcester arrived at Shrewsbury on 21 July 1403, where they encountered the king with a large army. The ensuing Battle of Shrewsbury was fierce, with heavy casualties on both sides but, when Henry Percy himself was struck down and killed, his own forces fled.
The circumstances of Percy's death differ in accounts. The chronicler Thomas Walsingham stated, in his Historia Anglicana that "while he led his men in the fight rashly penetrating the enemy host, [Hotspur] was unexpectedly cut down, by whose hand is not known". Another account states that Percy was struck in the face by an arrow when he opened his vizor for a better view. The legend that he was killed by the Prince of Wales seems to have been given currency by William Shakespeare, writing at the end of the following century.
The Earl of Worcester was executed two days later.
King Henry, upon being brought Percy's body after the battle, is said to have wept. The body was taken by Thomas Neville, 5th Baron Furnivall to Whitchurch, Shropshire for burial. However, when rumours circulated that Percy was still alive, the king "had the corpse exhumed and displayed it, propped upright between two millstones, in the market place at Shrewsbury". That done, the king dispatched Percy's head to York, where it was impaled on the Micklegate Bar (one of the city's gates). His four-quarters were sent to London, Newcastle upon Tyne, Bristol, and Chester before they were finally delivered to his widow. She had the body buried in York Minster in November of that year. In January 1404, Percy was posthumously declared a traitor, and his lands were forfeited to the Crown.
Henry Percy (Hotspur)