10 May 1318: The Battle of Dysert O'Dea was fought on this day. It took place near near Corofin, Co Clare. The battle occurred during the Bruce Invasion of Ireland.
The Anglo Norman Lord Richard De Clare ( a descendant of Strongbow) attacked the Irish chieftain Conor O’Dea, chief of the Cineal Fearmaic people and the ally of King Muircheartach O’Brien of Thomond. [North Munster]
De Clare made the mistake of dividing his army in three in the face of the enemy and he led the van towards Castle Dysert O’Dea – the home of the Irish Chieftain. O’Dea held them at the ford of Fergus and sent messengers out to bring up reinforcements as De Clare charged at his opponents only to be surrounded and cut down by the axe of Conor O’Dea himself.
As the rest of the Anglo Norman force came up they waded into the Irish and were on the point of extracting a bloody revenge when Felim O'Connor's troops charged down the hill of Scamhall (Scool) and cut a path through the English to join the battle. De Clare's son then arrived on the scene and was cut down and killed by Felim O'Connor.
As the two forces were locked in this deadly struggle both expected reinforcements to arrive and as King Muircheartach O'Brien’s men galloped onto the scene Conor O’Dea almost lost heart not knowing who they were until he heard the Irish war cries and knew the victory was won. Soon Lochlann O'Hehir and the MacNamaras joined the fight and it was all over for the Anglo Normans who sold their lives dearly and went down fighting.
The power of one of the great Anglo Norman families - the De Clares - was shattered forever. In the wake of this victory King Muircheartach O'Brien advanced upon the environs of Bunratty Castle, home of the De Clare Family to find much of the surrounding dwellings burnt by De Clare’s widow who promptly fled to England. The Castle though held out for a couple of weeks and the Irish completely destroyed it in 1322. The De Clare’s never returned and Thomond west of the Shannon remained under Irish rule until the early 17th Century. It was the greatest Gaelic victory of the Bruce War.