Birr

Birr grew near the meeting of the Camcor and Little Brosna rivers, in the lands of the O'Carrolls of Éile. An early monastery associated with Saint Brendan gave the place a religious importance long before the rise of the castle. The O'Carroll stronghold stood beside a settlement whose river valleys opened towards the Shannon, on the borderlands between Munster and Meath. Monastic learning and Gaelic lordship left successive marks on this inland town.

In the 1620s, the Parsons family took possession of the old fortress and developed the town under the name Parsonstown. Their arrival tied Birr to the plantation settlements reshaping the Irish midlands. The castle endured the wars of the seventeenth century, including a siege by Patrick Sarsfield in 1690, which failed to force its surrender. In the quieter eighteenth century, the Parsons turned their attention to the estate, while Birr developed the streets and houses of a prosperous market town.