What survives of this medieval church in Gaganstown, Co. Kildare amounts to a shallow rectangular hollow in the ground, roughly eight metres long and three metres wide, its eastern side lined with thin mortared flags. That is all that remains above ground. The site sits within a totally overgrown graveyard that also contains a medieval graveslab, and the whole lies within what was once Anfield Demesne. By 1837, a local historian could describe only "a very small portion of an old church"; by the twentieth century, even that fragment had largely disappeared into the earth.

The place carries a more layered history than its present condition suggests. The church is first recorded in 1179 under the name "Domnachmor an Athechda", and both that term, "Domhnach", and the later Irish "Teampull" are words associated with early Christian foundations predating the Norman arrival in Ireland. The area was once known as Yagostown, a name that derives from Jago or Yago, the Iberian form of James, and the townland of Gaganstown preserves a faint echo of that older identity. At the time, Jago was the name of a distinct parish in the Barony of South Naas, encompassing Gaganstown, Moorhill, Boleybeg, and Ardinode, before being absorbed into the parish of Ballymore Eustace. Local tradition holds that pilgrims who had successfully completed the long journey to Santiago de Compostela in Spain, the great shrine of St James, returned home and contributed to the building and upkeep of the church. Whether that tradition reflects an actual pattern of patronage or is simply a folk explanation for the dedication to St James is impossible to say now, but it gives the site an unexpectedly international dimension. The church and chancel were still described as being in good repair in 1615, yet within fifteen years, by 1630, they were already recorded as ruins. Nearby, a place name, "Cúl a Teampuill", meaning roughly "the back of the church", survived in local use and was associated with a tradition of a castle having once stood close by.