Gwenllian of Wales

Gwenllian's uncle, Dafydd ap Gruffudd, assumed her guardianship, but on 21 June 1283, he was captured with his family at Nanhysglain, a secret hiding place in a bog by Bera Mawr in the uplands of northern Wales.

Gwenllian and the daughters of her uncle Dafydd ap Gruffudd were all confined for life in remote priories in Lincolnshire and never allowed freedom.

[6] In committing her to a convent, Edward's aim was partly to prevent her from becoming a focus for Welsh discontent, perhaps by marrying and having sons who might lay claim to the Principality of Wales.

When writing to the Pope, attempting to secure more money for Sempringham Priory from the Church, the English king stated that "...herein is kept the Princess of Wales, whom we have to maintain".

The date of his death is unknown, but it was after 1305, when the King of England ordered a cage made of timber, bound with iron, in which to hold Owain ap Dafydd more securely at night.