Courcy, John de (a.1155–1219), magnate, was younger son of William de Courcy II and Agnes de Rumilly. He is one of the most colourful figures of the late twelfth century in Ireland, traditionally described as a landless knight from Somerset who, almost single-handedly, carved out a lordship in Ireland for himself in 1177. More recent scholarship has argued that while his family's main holdings were in Somerset, they also had holdings in the north-west of England, and that John de Courcy was familiar with the politics of north-eastern Ireland long before he set foot in the new colony. He may have first come to Ireland with Henry II (qv) in 1171, when the king is said to have given him a speculative grant of the kingdom of Ulaid. The veracity of this story is unclear; his first documented presence in Ireland is in 1176 when he journeyed there, leading a small force of ten knights, with William fitz Audelin (qv), newly appointed agent of the king. De Courcy appears to have chafed under fitz Audelin's cautious policies and found support among the Dublin garrison. In early 1177 he recruited a force (22 men-at-arms and 300 other soldiers, according to Gerald of Wales (qv)) from the garrison, marched north against fitz Audelin's wishes, passed through the kingdom of Airgialla (Co. Louth), and descended on Down, the main town of the kingdom of Ulaid. On 1 February 1177 de Courcy defeated a force led by Ruaidrí Mac Duinnsléibe (qv) (d. 1201), king of Ulaid, and took possession of the town. In June 1177 he defeated a larger force led by Máel Sechlainn Mac Lochlainn, king of Cenél nEógain, and secured his hold on his new lordship.
He was a skilled propagandist, bolstering his victory with claims that it had been foretold by prophecy. He also became a great defender of Armagh and St Patrick (qv), even commissioning a life of the saint to be written in 1186. While his devotion to the saint seems genuine, it was also politically motivated, as he was determined to promote Armagh as the primatial seat over Dublin. Whether it was his intention to create an independent lordship in Ulster or not, de Courcy recognised the authority of John (qv), lord of Ireland, by 1185, removing Ulaid from the lordship of Ruaidrí Ua Conchobair (qv), king of Connacht, who had held it by the treaty of Windsor. He adapted to the Gaelic political and military system quickly, leading raids that expanded his lordship beyond the traditional bounds of Ulaid, raiding as far west as Derry by 1197. But after the initial conquest, Ulaid remained peaceful and benefited from his good lordship. He also intervened in the politics of Connacht: in 1188 he brought troops to fight for Ruaidrí Ua Conchobair against his son Conchobar Máenmaige Ua Conchobair (qv) (d. 1189). He may have been appointed justiciar by John, lord of Ireland, in 1185, but this is uncertain; he was made justiciar by Richard I after John forfeited Ireland in 1194, serving jointly with Walter de Lacy (qv) till sometime in 1195. In 1195 he and Hugh de Lacy (qv) led an army to Athlone and negotiated a peace with Cathal Crobderg Ua Conchobair (qv), king of Connacht. His marriage (1180) to Affrica (qv), daughter of Godred, king of Man, allowed him to forge alliances with several important figures of the northern Irish Sea region; and many of the settlers whom he introduced came from the north-west of England. Similarly his monastic foundations (or in some cases refoundations) and benefactions relate to these links within the northern Irish Sea world. Downpatrick priory was granted to the monks of Chester and Nendrum in Down to St Bees in Cumberland (a dependency of St Mary's in York), while Affrica founded Grey Abbey, also in Down, from the Cistercian house in Holmcultram, Cumberland.
De Courcy's independent stance and diplomatic entanglements eventually caused his downfall. While Henry II and Richard I were willing to ignore his activities, John was not. In 1201 de Courcy led a force into Connacht to support Cathal Crobderg against his cousin Cathal Carrach Ua Conchobair (qv), but was forced to retreat, and on returning to Meath he was arrested by Hugh de Lacy and imprisoned. He was released to stop his followers raiding into Meath and was offered a safe conduct to the king, which he refused. De Lacy invaded Ulaid in 1203 and captured de Courcy. He was again freed, but this time de Lacy took hostages to ensure he would come before the king. He again ignored the royal summons and in 1204 de Lacy was again forced to invade Ulaid and capture him. He was freed on the promise that he would take the cross and travel to Jerusalem, but once again he failed to comply. His lands were confiscated and given to Hugh de Lacy on 29 May 1205 after he ignored the king's final summons. He joined with his brother-in-law Reginald, king of Man, to raid his former lordship, but had no success.
De Courcy was allowed to return to England in November 1207 and seems to have been reconciled with the king, as he returned with John to Ireland in 1210. John used him against de Lacy on that expedition, but never restored him to his Irish lands, and de Courcy seems to have remained in England till his death in 1219. His career clearly shows that he was an extremely capable soldier and a more than competent lord; his downfall was his inability to assess the temperament of the new king after 1199 and adjust his activities accordingly.