The medieval nave and chancel, built of uncoursed rubble limestone, was absorbed in 1780 by a Church of Ireland building, which was itself altered again in the nineteenth century, when the nave walls were thickened, the chancel arch shortened, and a west tower added. The result is a layered ruin where a pointed chancel arch was reduced to a smaller round arch, probably repurposed as a window for the later building, and where flat lintelled mural stairs in the north wall hint at an earlier tower that no longer survives. At the centre of the chancel, mortuary crypts fill the floor space, and the whole structure is ivy-covered and largely unroofed, caught somewhere between monument and slow dissolution.

The settlement around the church has its own complicated past. Writing in 1904 and 1905, the antiquarian Thomas Johnson Westropp described Caherconlish as once a walled town with four castles and the ruins of a collegiate building, its fortified gate standing until shortly before 1826. The place appears in records as early as 1259, and in 1285 to 1287 it was attacked by Torlough O'Brien, king of Thomond, whose forces stormed and burned the castle and plundered the church. Later records show the town receiving murage grants, a form of royal tax levied to fund the construction or repair of town walls, described in the Close Rolls as lying on the marches with Irish rebels on every side. A charter of Edward III survives dated 9 November 1358. The antiquary Thomas Dineley sketched the church in 1680 or 1681, capturing the roofed nave with its round-headed west doorway, a cruciform slit window, stepped battlements on the chancel, and a double bellcote rising above the roofline. Inside, he noted the monument to Theo. Bourke and his wife Slaney Brien, dated 1641, along with memorials to Annabel Gould and the relatives of John Maunsell, 1662.

The church sits at the northern edge of a burial ground enclosed by a circular stone wall, with its entrance gate to the south-east. A tower house castle associated with Caherconlish once stood just outside the burial ground to the south-west, though the relationship between the two structures is now largely legible only through the historical record and Dineley's sketch. The chancel is the more ruined portion; look for the long and short quoins on the south-east angle, some of them in sandstone rather than limestone, which points to earlier or repaired fabric. By 1840 only a fragment of the east end remained standing, roughly 3.65 metres high and 2.1 metres long, propped by a vault beneath it.