Hugh de Lacy, 1st Earl of Ulster

Hugh de Lacy, 1st Earl of Ulster (~1176 – after December 26, 1242) was the younger son of Hugh de Lacy, Lord of Meath. He was a leading figure in the Norman invasion of Ireland in the 12th century. He was created Earl of Ulster in 1205 by King John of England.

Circa 1189 he was appointed Viceroy of Ireland, a position previously held by his father. He was replaced in 1190 by Guillaume le Petil. He was later reappointed to serve as viceroy from 1205 to 1210.

He erected a motte in the 1180s in Carlow, on the site of which Carlow Castle was built in the 13th century. Excavations at Carlow Castle in 1996, found the remains of a series of post-holes inside a curving ditch, running under the walls of the towered keep and therefore pre-dating it. The remains of a corn-drying kiln were found to the north of this. These features were interpreted as representing the remains of the first castle here, whose defences and buildings seem to have been constructed of earth and timber. A reinterpretation of the historical sources suggests that this primary timber castle was built in the early 1180s by Hugh de Lacy for John de Clahull.

In 1199, King John of England authorised de Lacy to wage war on John de Courcy, who had conquered much of Ulster without help or permission from the King. Hugh captured de Courcy in 1204. An account of the capture appears in the Book of Howth.

In 1205 King John created him Earl of Ulster and made what was de Courcy's territory in Ulster the Earldom of Ulster. He granted Drogheda its charter. He continued the conquest of the north-eastern over-kingdom of Ulaid, building on de Courcy's success, with the earldom spanning across the modern counties of Antrim and Down and parts of Londonderry.

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