It is an easy thing to walk past without registering what it is: a fragment of a building that was already described as being "in repayre" in 1615, long before the present Church of Ireland structure replaced it in the late eighteenth century.

The parish of Finnoe, whose name may derive from the Irish for "woods", appears in ecclesiastical taxation records for the Diocese of Killaloe as early as 1302. The medieval church had a sometimes turbulent administrative life: in 1414 a papal document reassigned the rectory to Cornelius Chamly, also known as O'Hanly, on the grounds that the previous holder, William O'Hanly, had occupied it for more than a year without taking holy orders. By 1615, the Royal Visitation found only a church, no chancel, served by one Peter Butler as clerk and reading minister, with the rectory and vicarage together valued at fifteen pounds. The Civil Survey of 1654 to 1656 recorded the parish tithes as worth thirty pounds in the year 1640, and noted two acres of glebe land, a small plot attached to a church living, lying east of the churchyard and described as "at present wast". The church that replaced all of this was built in 1794 by a mason named Peter Stokesberry, who left a stone plaque on the south wall near the southeast angle of the building with the inscription: "Built by me Peter Stokesberry Mason A:D 1794". The present church was almost certainly raised on the footprint of its medieval predecessor, and fragments of that earlier fabric may be worked into both the church walls and the surrounding graveyard enclosure, though the chamfered window stone at the entrance stile is the most clearly identifiable survivor. By the early 1950s, a local account noted that no visible remains of the ancient parish church could be seen, the site having been absorbed entirely into the later building and its grounds.

The graveyard contains eighteenth and nineteenth-century headstones, and the church occupies the western quadrant of the enclosure. Visitors looking for the medieval stone should check the entrance stile at the southern boundary, where the reused jamb stone sits quietly in the fabric of the wall, carrying the only legible trace of the church that preceded everything else here.