Siege of Harlech
Who Fought
Henry, Prince of Wales commanded the besieging English force; the castle was defended by Glyndŵr's garrison, which included Edmund Mortimer.
History & Significance
Sir Edmund Mortimer IV (10 December 1376 – January 1409) was an English nobleman and landowner who played a part in the rebellions of the Welsh leader Owain Glyndŵr and of the Percy family against King Henry IV, at the beginning of the 15th century. He perished at the siege of Harlech as part of these conflicts. He was related to many members of the English royal family through his mother, Princess Philippa, Countess of Ulster, who was a granddaughter of King Edward III.
Edmund IV was born on 10 December 1376 at Ludlow Castle in Shropshire as the second son of Edmund Mortimer, 3rd Earl of March, by his wife, princess Philippa Plantagenet. He was a grandson of prince Lionel of Antwerp, Duke of Clarence, thus a great-grandson of King Edward III. His grandfather Lionel was previously married to Violante Visconti, sister of Gian Galeazzo Visconti, the Duke of Milan. Both were members of the House of Visconti and the Royal House of Savoy.
Edmund Mortimer had an elder brother, Roger Mortimer, 4th Earl of March, and two sisters, Elizabeth, who married Henry 'Hotspur' Percy, and Philippa, who married firstly John Hastings, 3rd Earl of Pembroke, secondly Richard Fitzalan, 11th Earl of Arundel, and thirdly, Sir Thomas Poynings.
Edmund was financially well provided for, both by his father, who died when Edmund was 5 years old, and by his elder brother Roger.
Edmund was a supporter of his cousin, Henry Bolingbroke, later King Henry IV of England, in spite of the fact that his older brother Roger had a stronger genealogical claim to the throne by reason of the fact that he and his brother were grandsons of Lionel of Antwerp, King Edward III's second surviving son, whereas Bolingbroke's father, John of Gaunt, 1st Duke of Lancaster, was King Edward III's third surviving son.
When his elder brother Roger was slain in a skirmish at Kells in Ireland on 20 July 1398, Edmund became responsible for protecting the interests of Roger's young son, Edmund Mortimer, 5th Earl of March, who also had a claim to the throne as heir to his father.
Both Edmund Mortimer and his brother-in-law Henry 'Hotspur' Percy fought for Henry IV against the Welsh rebel leader Owain Glyndŵr. However, at the Battle of Bryn Glas on 22 June 1402, Mortimer was defeated, allegedly because some of his Welsh forces defected, and he was taken prisoner.
King Henry's suspicions were fuelled by rumours that Mortimer had fallen into captivity by his own design. He forbade the Percys to seek their kinsman's ransom, and by October 1402 began seizing Mortimer's estates, plate and jewels. Mortimer thereupon transferred his allegiance to Glyndŵr. On 30 November 1402, he married Glyndŵr's daughter Catrin, and on 13 December 1402 proclaimed in writing that he had joined Glyndŵr in his efforts to restore King Richard II to the throne, if alive, and if dead, to make his nephew Edmund Mortimer, 5th Earl of March, King of England.
The ground they fought on
The site of Siege of Harlech lies on Lower Cambrian Rocks (Undifferentiated), bedrock that formed in the Early Cambrian. The rock here is sandstone and conglomerate, interbedded.
Edmund Mortimer, who had allied himself with Glyndŵr by marrying his daughter Catrin in November 1402 and signing a written proclamation of support the following month, was by the time of the siege reduced to great distress within the castle walls; he perished there, killed in the fighting, and his widow and daughters were subsequently taken into royal custody in London.
- Edmund Mortimer was killed in the fighting during or shortly after the siege. No further casualty figures are given in the sources.
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- Edmund Mortimer (rebel) · Wikipedia
- Glyndŵr rebellion · Wikipedia