Earldom of Ulster

The Earldom of Ulster was an Anglo-Norman lordship in northern medieval Ireland, established by John de Courcy from the conquest of the province of Ulaid in eastern Ulster. It was the most important Anglo-Norman lordship in the north of Ireland. At its greatest extent it extended as far west as the Inishowen peninsula in modern-day County Donegal, which was at one time the power-base of the Northern Uí Néill.

The Earldom of Ulster suffered heavily from the Bruce campaign in Ireland in the 1310s, from which it never recovered. By the 15th century the earldom was restricted to coastal enclaves in County Down and Carrickfergus, and the title of Earl of Ulster had passed to the Crown in 1461.

In 1175 after a period of fighting between the Normans and Irish, the Irish High King, Rory O'Connor sued for peace with King Henry II of England, who agreed to a status quo, allowing the Normans to consolidate their conquests in return for no more incursions into Gaelic territory. Henry's Norman vassals however remained restless. In 1176, John de Courcy came to Ireland alongside William fitz Audelin, Henry II's deputy. Around the start of 1177 de Courcy went about carefully planning an invasion of Ulaid in eastern Ulster. Having acquired the approval of the royal governor in Dublin, de Courcy took 32 mailed horsemen and some 300 foot soldiers north into Meath, where he had obtained the right of passage through from its lord, de Lacy. He then met up with Irish allies who helped provide men and information for the invasion. De Courcy's force then advanced beyond the northern extent of Norman control and into Ulaid, reaching the petty-kingdom of Lecale having only set out from Dublin four days before. Until this, Ulaid had been untouched by "English" forces.

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