In Shakespeare's play, Henry IV, Part I, King Henry has made plans to travel with his army to the Holy Land to try to end the war there, in joining the Crusades. However, trouble at home prevents him from doing so, and Henry cancels his plans, turning his attention to matters within his own country.
In the play, there are rebellions taking place in England, specifically in Wales and Northumberland. Geographically, Northumberland is located in the northeastern part of England, below Scotland, while Wales is located at the southwestern corner of the island. They are in opposite directions.
Northumberland has a history of revolt and rebellion against the government, as seen in the Rising of the North in Tudor times. These revolts were usually led by the then Dukes of Northumberland, the Percy family. Shakespeare makes one of the Percys, the dashing Harry Hotspur, the real hero of his Henry IV, Part 1.
Wales is located farther south on the island of Britain.
Llywelyn ap Gruffydd's death in 1282 marked the completion of Edward I of England's conquest of Wales...Owain Glyndŵr briefly restored independence to what was to become modern Wales, in the early 15th century. Wales was subsequently annexed by England under the Laws in Wales Acts 1535–1542 since when, excluding those matters now devolved to Wales, English law has been the legal system of Wales and England.
In reference to the geographical sites of unrest and rebellion in Shakespeare's play, Henry IV, Part I, the fighting takes place in the far northern part of Britain, just below Scotland, and in the lower corner of the country, on the southwestern side.