princes of gwynedd



Also known as: Joan, Siwan, Lady of Wales

Joanna was the illegitimate daughter of King John of England, sometimes called John Plantagenet because his family was from the House of Plantagenet. Little is known about Joanna's early life but it is believed she spent some time in France. She was betrothed to Llewelyn ap Iorwerth when King John hoped the marriage would bring peace between England and Wales as he was fighting the French and didn't want to have to fight the Welsh at the same time. The marriage took place in May 1206 at Chester when Joanna was about 15.

The peace between England and Wales was rocky and Joanna proved a worthy political diplomat; she acted as mediator between her father King John and Llewelyn on more than one occasion. At one stage Joanna sent a letter to her father which saved the life of her step-son Gruffydd when King John hanged the other prisoners held with Gruffydd.

In 1230, Joanna was accused of adultery with William de Braose. William was hanged and Joanna was banished for a year before Joanna and her husband were reconciled.

On her death, her husband founded a priory at Llanfaes in her memory. Her coffin now resides in Beaumaris Church.

List of all Characters

Llewelyn ap Iorwerth

Fought to unite Wales and became known as Llewelyn the Great.
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Wife of Llewelyn ap Iorwerth and mediator between the Welsh and her father, the English King. (You are on this page).

Dafydd ap Llewelyn

The first person to claim the title ‘Prince of Wales’.
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Gruffydd ap Llewelyn

The overlooked eldest son whose resentment led to tragic results.
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Llewelyn ap Gruffydd

The first Prince of Wales recognised as such by the English and known to the Welsh as ‘Our Last Leader’.
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The Successors

What happened to the successors to the title of Prince of Gwynedd and Prince of Wales?
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Contact Information

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