The castle was granted to Sir Nicholas Walshe in 1587, during the Tudor conquest of Ireland when English and Anglo-Norman families were consolidating their power across the country. By 1641, the castle remained in Walshe family hands, though the Civil Survey conducted around 1655 paints a picture of decline, describing it as already ruined despite still maintaining its large bawn (a fortified courtyard), an orchard, a pigeon house, and several cabins.

Today, what remains of Ballykeeroge Castle is far more modest than its former glory. The site consists primarily of a cairn of rubble measuring approximately 22 metres by 9 metres and standing 2 to 3 metres high. Among these ruins, two chamfered and rebated limestone jambstones from what was once a pointed doorway serve as the most distinctive architectural remnants, offering a tangible connection to the castle’s medieval construction techniques. These carved stones would have framed an entrance, their careful shaping and decoration indicating the importance of the structure they once supported.

The castle’s decline mirrors the broader narrative of many Irish fortifications from this period. By 1778, it appeared on Taylor and Skinner’s maps as a ruin, suggesting it had been abandoned for some time. The archaeological record, compiled from the Archaeological Inventory of County Waterford and updated through recent research, provides these glimpses into a site that once served as both a defensive structure and a symbol of authority in medieval and early modern Waterford.