The original castle was constructed during the reign of Elizabeth I, somewhere between 1558 and 1603, by the Crosby family. This fortress appears on a 1563 map of Leix and Offaly, marking it as an important stronghold in the region during the Tudor period. In 1666, the castle passed into the hands of Piriam Pole, though it wouldn’t survive much longer in its original form.

William Pole, Piriam’s son, made the dramatic decision to demolish his father’s castle entirely and construct a new house on the same site. This replacement building would itself eventually give way to the current Ballyfin House, an impressive Georgian mansion built between 1821 and 1826. Today, no visible traces remain of the original Elizabethan castle; its stones and foundations have been completely absorbed by centuries of reconstruction and landscaping.

The site represents a common pattern in Irish architectural history, where medieval fortifications gave way to more comfortable domestic dwellings as the country became more politically stable. Located in County Laois, Ballyfin Demesne continues to be significant as an example of how Ireland’s built heritage evolved from defensive structures to grand country houses, even if the earliest chapter of that story now exists only in historical records and old maps.