What makes Burrishoole quietly strange is not simply its state of preservation, but the layered evidence of everything it was asked to be across the centuries: a place of mendicant poverty, aristocratic patronage, military garrison, and eventually, ruin used as graveyard. Two gunloops cut into the wall of the south chapel sit a few feet from a finely carved stone altar, and that juxtaposition says most of what needs saying about the building's history.

The priory was founded in 1469 by Richard Bourke of Turlough, known in Irish as Risteard an Cuarscidh, Richard of the Curved Shield, who had been elected Mac William Íochtar, chief of the Mayo Bourkes, in 1460. Having established the house for the Dominicans, a mendicant order whose friars relied on alms rather than endowments, he resigned his lordship, took the habit, and died within the community in 1473. The foundation was almost immediately controversial: the Archbishop of Tuam had granted permission without obtaining papal approval, leaving the friars exposed to the threat of excommunication. That uncertainty lasted until 1486, when Pope Innocent VIII issued a bull regularising the priory and formally authorising a church, steeple, bell, cloisters, dormitories, and refectory. Patronage continued under the next generation. A gilt silver chalice now in the National Museum, dated by inscription to 1494, was commissioned by Thomas de Burgo, Richard's grandson, and his wife Grania Ni Malle, an O'Malley, the two great families of the territory bound together in an object of considerable craft. The priory sat within the territory of Umhall, a region defined at the time by intermarriage and rivalry between the Gaelic O'Malleys and the Anglo-Norman descended Bourkes, and Burrishoole was very much a product of that entanglement. By 1580, after the Dissolution of the Monasteries had theoretically closed such houses, Sir Nicholas Malby, Governor of Connacht, had taken possession and wrote an inventory of the location's strategic and economic worth that reads less like an ecclesiastical survey than a prospectus: timber, grey marble, an iron mine, fifty English fishing vessels arriving annually, and a river deep enough at low tide to take a ship of five hundred tons. He garrisoned the buildings, which explains the gunloops. In 1606 James I granted the abbey to John Kinge of Dublin, who sold it immediately to Michael Cormick of Innishmayne. Cromwellian troops occupied it in 1653. A handful of Dominican friars continued working in the area through the 17th century, and by the 18th century the structure had become a ruin, though it retained its function as a burial ground and a site of local devotion.

The ruins reward close attention to the building sequence. The nave and chancel came first, then the south chapel and cloister were added, the tracery window in the chapel closely matching the east window of the chancel in style, suggesting the gap between phases was short. The crossing tower came last, inserted at the junction of nave and chancel and partly blocking an earlier archway. In the vault of that tower, two holes for bell ropes are still visible overhead, and on its east face the ghostly outline of the original steep-pitched chancel roof is pressed into the stone. The stone-built altar in the north recess of the south chapel remains intact, and corbels at the base of the tower piers are the remnants of a small table altar. Just inside the west doorway, a holy water stoup sits on a free-standing octagonal pillar, still in place after five and a half centuries.