In the churchyard next to St James' Church of Ireland church lies the ruins of an earlier church. The oldest part of the ruin appears to date to the early thirteenth century. Thomas FitzAnthony had just established the town of Stradbally and a two-celled building seems to have served as the settlement's church. Most likely it belonged to the Augustinian Priory of Canons Regular at Inistioge, Co. Kilkenny -- the Priory owed Stradbally church in 1540 and since the Priory too was founded by Thomas FitzAnthony, the relationship between the religious houses probably stretches back to the church's thirteenth century foundation.
The nave of the ruined church dates from the early thirteenth century and is the oldest part of the ruin. The chancel and tower were added later. The tower was constructed sometime between the 13th century and the post-medieval period, and appears to have been the priest’s residence, rather than a belfry — another rare example of an inhabited tower is seen at Inistioge Priory.
After the Reformation Stradbally church was confiscated by the English Crown and thus came under the control of the Protestant bishops of Waterford and Lismore. Meiler McGrath, the Protestant bishop of the diocese of Waterford and Lismore (a clergyman with a colourful career, who switched between being a Catholic and a Protestant when it suited him) carried out a survey of his diocese for the Crown.
Stradbally church would have been closed down under the Cromwellian regime (1650-60). It was possibly reopened during the reign of the Catholic James II, but was certainly ruined by the 18th century, where graves dating to early on in the 18th century began to be dug inside the church. Catholic burials appear to have continued around the ruin in this period.