Montgomery Montgomeryshire United Kingdom

Llywelyn ap ap Gruffydd had launched a campaign after Simon de Montfort's death in order to rapidly gain a bargaining position before King Henry had fully recovered.

Llywelyn had captured Hawarden Castle in 1265 and routed the combined armies of Hamo Lestrange and Maurice fitz Gerald in north Wales.

Llywelyn had then moved on to Brycheiniog, and in 1266, had routed Roger Mortimer's army.

With these victories and the backing of the papal legate, Ottobuono, Llywelyn had opened negotiations with the king, and is eventually recognized as Prince of Wales by King Henry in 1267 in the Treaty of Montgomery.

In return for the title, the retention of the lands he had conquered and the homage of almost all the native rulers of Wales, he is to pay a tribute of twenty-five thousand marks in yearly installments of three thousand marks, and can, if he wished, purchase the homage of the one outstanding native prince—Maredudd ap Rhys of Deheubarth—for another five thousand marks.

However, Llywelyn's territorial ambitions gradually make him unpopular with some minor Welsh leaders, particularly the princes of south Wales.