in 1489, Henry planned to aid Brittany in maintaining independence so that Britain could have a foothold and ally in France. a vote by parliament agreed to give henry a £100,000 subsidy to fund this, but it had to be raised through taxation
people resented this as it was an early from of income tax, whereas many prior taxes were paid in kind. only 27,000 pounds were raised, and given that Yorkshire's economy had been hit by a bad harvest, people saw this as a step too far.
Yorkshire residents hated this as they were previously exempt from these kinds of taxes as they were expected to use their finances to defend the northern border against the scots.
people appealed to Henry Percy (Earl of Northumberland), who brought it up with henry. henry believed he needed to assert his authority and believed helping brittany would benefit england in the future, so he did not make any changes
when the earl of Northumberland returned to Yorkshire with no changes, he was killed, as people believed he was lying due to him having been a supporter of the tax and wanting to keep a positive relationship with Henry.
because of this, Sir John Egremont, an illegitimate member of the House of Percy, led riots over the tax, but fled to Flanders when faced with the royal army led by the Earl of Surrey, showing he was an unreliable leader
Henry travelled North and issued many pardons to rebels as a conciliatory gesture.
Surrey was appointed as Lieutenant of the Council of the North, meaning Henry had no more problems up north as the Earl of Surrey was loyal as he owed his social and political advancement to Henry.
despite Henry eradicating the threat and lands that belonged to the earl of Northumberland being transferred to the crown, henry still failed to collect the region's tax quota for the Brittany campaign