Following the conquest of Brycheiniog by Bernard de Neufmarché in the late 11th century, and its conversion into his Lordship of Brecknock, the whole of Cathedine was initially assigned by him to his prisoner Gwrgan ap Bleddyn, son of the last king of Brycheiniog (Bleddyn ap Maenarch) but was later repossessed by Bernard. From the late 12th century formed part of the medieval Marcher lordship of Blaenllynfi (of which Talgarth was the main town), which eventually came into the possession of Gwrgan's descendant, Rhys ap Hywel (ancestor of Sir Dafydd Gam).