Rathgar Castle, as it was known, became associated with the Cusack family in the early 1600s and found itself caught up in the tumultuous events of the Battle of Rathmines in 1649, when Cromwell’s forces clashed with Royalist troops during the Irish Confederate Wars.

By the late 18th century, the castle had fallen into picturesque ruin, though it still impressed those who came to document it. The artist Gabriel Beranger visited in 1769 and sketched what remained: a double gabled structure attached to a courtyard, its walls still imposing despite their decay. He was particularly struck by the thickness of the walls, noting that they were so substantial they contained staircases built within them; a testament to the defensive architecture of the period. Austin Cooper, visiting in 1782, described in his diaries the remnants of what had clearly been a large and extensive building.

Today, no visible trace remains of Rathgar Castle above ground. The site has been completely absorbed into Dublin’s suburban landscape, with modern roads and buildings covering any physical remnants of this once impressive fortress. Yet its memory persists in historical records and the drawings of those 18th century antiquarians who recognised its significance before it vanished entirely from view.