Its presence there is easy to overlook, but the inscription it carries makes it something worth pausing over: a line of Irish text dating to 1627, recording that Cormac Mac Aodhagáin made the work in that year.

The stone came originally from Park Castle, the seat of the Mac Egan family, who held the hereditary role of brehons to the O Conors of Connacht. A brehon was a professional jurist in the Gaelic legal tradition, responsible for interpreting and applying the ancient system of Irish law known as Brehon Law, and certain learned families passed this function down through generations. The Mac Egans were among the most prominent of these dynasties, their legal authority closely tied to the O Conors as one of the great ruling families of Connacht. By 1627, the Gaelic order they had served was under severe pressure following the upheavals of the late sixteenth and early seventeenth centuries, yet Cormac Mac Aodhagáin still saw fit to commission this stone and mark it with his name and the date in his own language. There is something quietly defiant in that act.

How or when the stone was moved from Park Castle into the schoolhouse wall is not recorded, but its survival is remarkable given the fate of many such objects. The inscription, in Irish, is a rare example of a craftsman or patron asserting identity through language at a moment when that identity was increasingly marginalised. Visitors to Clonbern who know to look for it will find the stone set into the fabric of a building whose later purpose, educating children, sits in an unintended but thought-provoking relationship with the legal and scholarly traditions the Mac Egans once represented.