A rupture, sudden and unaccountable? King John's welsh incursion of 1209 reconsidered
Kinesiology; Public Health and Recreation
Welsh History Review
Historians have sought to explain the breakdown in relations between Llywelyn ab Iorwerth and King John in 1210 in terms of Llywelyn's supposed adherence to William de Briouze, who was at that time in revolt against the king. This article postulates that relations between king and prince had begun to deteriorate as early as 1209, following Llywelyn's invasion of the lands of Gwenwynwyn in soudiern Powys at the end of 1208. It is proposed that John's Welsh incursion of 1209, which has hitherto been ignored or discredited by most historians, did in fact occur, and that its outcome had a crucial bearing on Llywelyn's thinking during John's Welsh campaigns of 1211.
Craig Owen Jones. "A rupture, sudden and unaccountable? King John's welsh incursion of 1209 reconsidered" Welsh History Review (2020): 1-18. https://doi.org/10.16922/whr.30.1.1