Dunamase Castle, Rock of Dunamase, Portlaoise, Ireland

Dunamase Castle is a defensive stronghold dating from the early Anglo-Norman period with a view across to the Slieve Bloom Mountains. The site was first settled in the 9th century when a hill fort or dún was constructed on the site. In 845 the Vikings of Dublin attacked the site and the abbot of Terryglass, Aed son of Dub dá Chrích, was killed.

The current castle was built in the second half of the 12th century. Who built it is not recorded, but Meiler Fitzhenry is the most likely candidate. Strongbow is another possibility, as it was he who controlled Leinster as heir of Dermot McMurrough. With the marriage of Strongbow’s daughter and heir, Isabel, the castle passed into the hands of the Marshal family. William Marshal, who later became Regent of England in the minority of Henry III, had five sons, all of whom succeeded him in turn and died without issue. So in 1247 the Marshal lands were divided among William’s five daughters. Dunamase fell to Eva Marshal and then to her daughter, Maud, who was married to Roger Mortimer. The castle remained in Mortimer hands until 1330 when another Roger Mortimer was executed for treason. By the time the Mortimer family was rehabilitated, the castle seems to have passed out of the area under Norman control. There is no evidence that the castle was taken over and used by the local Irish lords and it seems to have become a ruin by 1350.

There is no evidence that the castle was reoccupied in the 17th century. It played no part in the Cromwellian wars, except that it was blown up in 1650 to prevent it being used.