Llywelyn, Dafydd, and the road to Welsh war

The watch point sets up the wars behind the Ring of Iron by starting with Llywelyn ap Gruffudd's gains under the 1267 Treaty of Montgomery. Internal Welsh division matters immediately: Dafydd defects after a failed attempt against his brother, while Llywelyn refuses homage and plans to marry Simon de Montfort's daughter. Edward's 1277 army included thousands of Welsh opponents of Llywelyn, so the conflict cannot be reduced to a simple English-versus-Welsh national war. The Treaty of Aberconwy cuts Llywelyn back to Gwynedd but leaves him the title Prince of Wales and a viable realm. Tension then shifts from territorial conquest to government as Edward attempts to impose English law in the lands he controls. Dafydd, dissatisfied with his reward for supporting Edward in 1277, triggers the renewed conflict in 1282.