[3][4] This was an early monastic site, founded c. AD 800 by Saint Boedan (Baedán, Baetan) and then located in the kingdom of Uí Maine.

[citation needed] Clontuskert appears in the Calendar of Papal Petitions for 1379, where "Nicholas O’Quinaeych, Augustinian Canon of St. Mary’s Cluyctenagentomany [Clontuskert-Hy-Many]" was given a dispensation by Pope Urban VI to become prior of the monastery.

[10] The great west doorway features many carvings, including Michael the Archangel with a sword and the scales for weighing souls; Saints Augustine of Hippo, Catherine of Alexandria and John the Baptist; a pelican feeding her young; a pair of griffins; and a mermaid with a mirror.

The inscription reads MATHEV DEI GRA EPS CLONFERTENS ET PATRE ONEACDAVAYN CANONIE ESTI DOMINE FI FECERT ANO DO MCCCCLXXI (Matthew by the Grace of God, Bishop of Clonfert, and Patrick O’Naughton, canon of this house, caused me to be made in 1471); the bishop referred to is Matthaeus Mág Raith, the only Augustinian to hold the see of Clonfert.

[13] This abbey is mentioned as well in Lina Callejon’s novel "Ien Seu: El Camino" (Editorial Círculo Rojo)