Sir Robert FitzEustace, who died in 1486, held the manor of Ballycotelan, as Coghlanstown was then known, which boasted three castles in total. This particular fortification appears on Noble and Keenan’s 1752 map of County Kildare, positioned prominently near the religious buildings, though by the time Taylor created his map in 1783, the structure was already recorded as being in ruins.

The castle’s association with the FitzEustace family places it within the broader context of Anglo-Norman settlement in Ireland. The FitzEustaces were influential landowners in medieval Kildare, and their manor at Ballycotelan would have been a centre of agricultural production and local administration. The presence of three castles within a single manor suggests considerable wealth and strategic importance, likely serving both defensive and residential purposes during a period when such fortifications were essential for maintaining control over territory.

Today, no visible trace of the castle remains above ground, leaving only historical maps and documents to tell its story. The site serves as a reminder of how dramatically the Irish landscape has changed over the centuries, with once-prominent fortifications disappearing entirely whilst their neighbouring churches and graveyards have endured. Archaeological investigation might yet reveal foundations or other subsurface features that could shed more light on this lost piece of Kildare’s medieval heritage.