In the Plantation of Ulster by grant dated 29 April 1611, King James VI and I granted "the town and lands of Gortatowill containing 6 polls, comprising a total of 300 acres at an annual rent of £3-4s., to Mulmore McHugh McFarrall O'Rely, gent". Mulmore O'Reilly had been dispossessed of his lands in the townland of Aghaweely Lower in the parish of Ballintemple. He was the grandson of the chief of the O'Reilly clan, Fearghal mac Seaán, who ruled East Breifne from 1526–1534. His genealogy is "Maol Mórdha son of Aodh son of Fearghal son of Seaán son of Cathal son of Eóghan na Fésóige". Mulmore O'Reilly had four sons by his wife Honora- Émonn, Hugh O'Reilly (Archbishop of Armagh) (b. 1580, d. 1653), Fearghal and Domhnall. He also had an illegitimate son, Cathaoir. Mulmore died sometime between 1611 and 1637. He left his lands in Tawnagh to his son Émonn (Edmund) O'Reilly. Émonn had three sons, Aodh (Hugh), Cathal and Brian. An Inquisition held in Cavan Town on 12 September 1638 found that the said "Edm’ Relly recently of Gortetowell in Co. Cavan, in his life, was seised of a poll of land called Tawnagh, and of a poll called Carrick in said county. The said Edmund died on 29 September 1637. Hugh O’Reyly, his son and heir has reached his maturity and now holds the land from the king in free and common socage. Catherine Newgent, alias Reily, was the wife of the said Edmund and the aforesaid Catherine is dower of the premises." At the outbreak of the Irish Rebellion of 1641 Hugh O'Reilly still held the townland according to the Books of Survey and Distribution. Hugh O'Reilly had two sons, Émonn and Phillip. Hugh's son Émonn had one son Sémus.