In 1611 he received 2,000 acres (810 ha) at Clancally (barony of Clankelly) in Fermanagh, and in 1612 he, with 39 others, appealed to the lord-deputy, Sir Arthur Chichester, to grant them jointly a part of County Sligo, 60,000 acres (24,000 ha) in Fermanagh, and some neighbouring territory, on their undertaking to expend £40,000 on the land, and to settle on it 1,000 "able men".
[5] He built Castlehasset on Lough Erne, a stone house and bawn known later as Crevenish Castle; and died there on 11 March 1624.
[7][8] By way of dedication, Blenerhasset made commendatory remarks about Thomas Leighton, Governor of Guernsey where he was stationed.
Blenerhasset's contribution to the Mirror was a continuation of Higgins's book, "from the conquest of Cæsar unto the commyng of Duke William the Conqueror".
[7][8] There 12 poems based on figures largely legendary: Guidericus (i.e. Guiderius), Carassus (i.e. Carausius), Queen Hellina (i.e. Helena, mother of Constantine I), Vortiger (i.e. Vortigern), Uter Pendragon (i.e. Uther Pendragon), Cadwallader (i.e. Cadwaladr), Sigebert (i.e. Sigeberht of East Anglia), Lady Ebbe (i.e. Æbbe the Younger), Alurede (i.e. Alfred the Great), Egelrede (i.e. Ethelred II), Edricus (?
The metre used is the iambic hexameter, and Blenerhasset is credited with the first explicit recognition of the classical iambus as a foot of verse in English.
Further, she identifies that set of ideas with the circle of Robert Sidney, 1st Earl of Leicester, suggesting that Blenerhasset aspired to membership of that group, as well as of the poets who followed Baldwin by looking for more than face value in the Mirror works.
His eldest brother, Sir Edward Blenerhasset, who shared with him several grants of Irish land, died in 1618.