The O'Neill family home here is believed to have begun its life as a chapel used by the monks of Jerpoint Abbey, a Cistercian foundation established in the twelfth century on the banks of the Little Arrigle river near Thomastown. That a domestic residence might preserve the bones of a monastic chapel is not unusual in Ireland, where the suppression of the monasteries in the sixteenth century left many religious buildings to be adapted, absorbed, or simply forgotten into the landscape.

The connection to Jerpoint runs deeper than the building itself. According to local historian O'Kelly, writing in 1985, the Abbeygrove townland was formerly part of Dunbell, which fell within the landholdings of Jerpoint Abbey. The abbey's estates were considerable, spreading across much of south Kilkenny, and the presence of a dependent chapel within that territory would have been entirely consistent with how Cistercian communities organised their outlying lands. When those lands eventually passed into other hands following the dissolution of the monasteries, the structures on them followed a familiar pattern: repurposed, rebuilt, or quietly absorbed into the fabric of later private ownership.