| 1400 | Aug | Glendower's revolt starts |
| | | What started as a land dispute between Owen Glendower, a wealthy land owner in Wales and his rival Lord Grey of Rutin quickly escalated to a revolt when the English King Henry IV sided with Rutin and awarded him the land. |
| Oct | Henry fights back against Glendower |
| | | Henry IV moved into North Wales to try and stop the rebellion but he was not able to deal with the Welsh rebels who were more skilled at fighting in the terrain. |
| 1401 | | Hotspur takes control in North Wales |
| | | Henry IV gave his son Prince Henry, the future Henry V, the task of defeating Glendower in North Wales. As the boy was only 13 years old, Hotspur a knight and jouster of importance was given the role of guardian over the Prince. Hotspur was the son of Henry Percy the Earl of Northumberland. |
| Jun | Hotspur resigns |
| | | After accusing the king of not paying his army, Hotspur resigned his guardianship of the king's son in North Wales and he left to resume fighting the Scots. |
| 1402 | | Henry IV assembles an army |
| | | The king assembled an army at Shrewsbury Castle in preparation to fight Owen Glendower. |
| Jun 22 | Battle of Pilleth |
| | | Edmund Mortimer's army met Owen Glendower at Pilleth near Whitton in central Wales. Mortimer's army was badly defeated and Mortimer was captured. Glendower offered to release Mortimer for a large ransom, but Henry IV refused to pay. |
| Sep 14 | Battle of Homildon Hill |
| | | The armies of the Percies and the Scots met at Homildon Hill near Wooler in Northumberland. The Scots were defeated and the Scots' leader the Earl of Douglas was captured. Henry IV wanted Douglas handed over but Hotspur refused. Hotspur was angry with the English king who had refused to pay a ransom for Edmund Mortimer who had been captured by Owen Glendower and who was a friend of Hotspur's. |
| 1403 | | Llansteffan Castle attacked by Glendower |
| | | The Norman Llansteffan Castle was attacked by Owen Glendower. Glendower may have held the castle for a short time until it was retaken by Sir John Penress (Pennes). |
| | Prince Henry in command |
| | | Prince Henry, now sixteen, took control of this army in Wales. He took his troops looking for Owen Glendower but could not find him and so burnt villages and killed any prisoners that were taken. Henry's main problem, like Hotspur's before him was that the King was not providing enough money to pay the English troops. |
| Jul 21 | Battle of Shrewsbury |
| | | Henry IV managed to reach Shrewsbury just before Hotspur arrived and the rebel army had to camp outside the town to the north. The battle lasted all day but it ended when Hotspur was killed. |
| 1404 | | Cardiff sacked by Glendower |
| | | Owen Glendower attacked and captured the town of Cardiff and its castle. |
| | Harlech Castle siege |
| | | The Welsh captured Harlech Castle and the fortess became the base for Owen's revolt. |
| May | Glendower's Parliament |
| | | Owen Glendower called a Parliament where he declared himself to be the true 'Prince of Wales'. Embassies from France and Scotland attended the meeting and gave promises to support Glendower's plans to overthrow Henry IV. |
| 1405 | Feb | Glendower's agreement |
| | | Owen Glendower, Edmund Mortimer and the Earl of Northumberland combine forces and share the same goal of removing Henry IV. They agreed to divide England and Wales in three, Owen taking Wales and the west of England, the Earl to take the north of England and the north Midlands. Mortimer could have the rest. |
| Spring | Battles of Grosmont and Usk |
| | | English forces fought and defeated Welsh forces in two battles at Grosmont and Usk. Sir John Talbot defeated Glendower at Grosmont and Prince Henry forced the Welsh to flee at Usk. Glendower's eldest son was captured at Usk and sent to the Tower of London where he died. |
| 1407 | | Harlech Castle siege |
| | | The English besiege the Welsh in Harlech Castle. |
| | Prince Henry besieges Aberystwyth |
| | | Prince Henry laid siege to the castle at Aberystwyth in an attempt to remove the Welsh who had captured it in 1404. |
| 1408 | Autumn | Aberystwyth falls to Henry |
| | | The Welsh surrender the castle at Aberyswyth. They had held out for a year. Prince Henry had tried destroying the castle with canons but had no success. |
| 1409 | Mar | Harlech falls to the English |
| | | The Welsh in Harlech Castle surrender to the English and the revolt of Welsh comes to an end. Edmund Mortimer was killed. |
