When the Plantation Commissioners reached Tyrone they found that all the lands in the area belonged to the Crown except the Church lands and about 5,000 acres which had been granted by Queen Elizabeth to Sir Henry Oge O’Neill. These lands comprised the ancient Irish territory known as Mointerburn, and were the inheritance of Sir Phelim Roe O’Neill of Kinnaird, on the Blackwater.

Of the Undertakers among whom the precincts of Omagh was divided the principal recipient was George Tucket, Lord Audley, who was granted an estate of 3,000 acres; but this favourite of James I., having neglected to erect castles and settle British subjects on the lands, according to the articles of plantation. The grant ultimately reverted to the Crown.

‘The Lord Audley,’ reports Sir George Carew, twelve months after the division of the lands of the Omagh lands, “has not appeared, l nor any for him; nothing done.” His Lordship had come from Audley, in Staffordshire, and was the eighteenth Baron Tucket. His 3,000 acres in Omagh included 2,000 for himself and 1,000 for his wife, Elizabeth who was the daughter of Sir James Mervyn, of Fonthill, Gifford, Wiltshire.

He was created Earl Castlehaven in 1616 but only lived a few months afterwards.

When this property was sold after his death it was found that, besides the original 3,000 acres of meadow, 3,000 acres of pasture land, 2,000 acres of wood, 2,000 acres covered the bramble and furze, and 200 acres of bog, all of which had been thrown in gratuitously to his proportion as waste and unprofitable lands.

A considerable proportion of the lands so granted to Lord Castlehaven and sold after his death, fell to the possession of Sir Audley Mervyn, brother-in-law of Colonel Rory Maguire who married Deborah, daughter of Colonel Audley Mervyn, and relict of Sir Leonard Blennerhassett.’