In 1609, Sir Robert Nugent of Walshestown received a land grant for the manor of Dysart, which included a castle, hall, and stone bawn, along with a lough, stable, two barns, a haggard, 40 messuages, 50 gardens, and a fish pond. Recent aerial photographs from 2011 reveal numerous earthworks in the fields surrounding where Dysart House once stood, particularly east of Dysart church and graveyard. These earthworks likely represent the remains of the castle and bawn mentioned in Nugent’s grant, though the house itself appears as ruins on Ordnance Survey maps from 1837.

The strategic importance of Dysart dates back even further, to the late 12th century when Hugh de Lacy retained personal control of the ‘lake and vill of Dysart’ whilst granting the surrounding barony of Magheradernon to William le Petit. This retention suggests Dysart held particular significance as a manorial centre for the Anglo-Normans. By the early 13th century, the lands had passed to William Pipard, son of Ralph Pipard, who held them under Walter de Lacy. The Pipard connection ended in 1301 when Ralph Pipard sold Dysart Manor to King Edward I, though by then the fortifications were already in decline; an inquisition held in 1302-03 described the site as possessing only ‘a small, weak, and ruined fort, which together with the messuage is worth nothing a year’.

The exact nature and location of these early fortifications remain somewhat mysterious. Rather than a traditional motte and bailey castle, the Anglo-Norman fort at Dysart may have been a ringwork, as no evidence of a motte-like earthwork has been found in the surrounding fields. About 420 metres south of the church and graveyard, archaeologists have identified three sub-triangular earthworks and field systems that could be connected to the medieval manor. The pond mentioned in de Lacy’s original grant may be the same water feature recorded in the 1609 grant to Nugent, located approximately 240 metres west of where Dysart House would later stand, providing a remarkable thread of continuity across more than four centuries of Irish history.