Ownership of the castle subsequently passed to Strongbow’s daughter, Isabel de Clare (d1220) who married William Marshal (d1219) who was created earl of Pembroke and was Regent of England following the death of king John. With none of his five sons producing an heir, the Marshal lands were divided among his five daughters, Dunamase being granted to Eva Marshal (d1246). She married William de Braose (d1230) and again, there being no sons, Dunamase passed to a daughter Maud de Braose (d1301) who married Roger Mortimer (d1282), baron of Wigmore. So the Mortimers came to own Dunamase after a succession of female-line descents. By the time the Mortimer lands were generally restored to the 2nd earl of March, following the execution of his grandfather, Dunamase seems to have passed out of Norman control. It was ruinous by 1350 but partially rebuilt later, before being reduced by Cromwell’s troops.

The main hall, or keep, dates from around 1200 and sits right on top of the rock. A curtain wall runs around the edge of the summit, enclosing the lower and upper wards which are accessed by a main gate. Protecting the main gate is a walled D-shaped enclosure with a barbican gate at the lowest point.