Grangefertagh is located about 3.3 km (2.1 mi) north of Johnstown, County Kilkenny, near a crossing-point on the River Goul.

[1] Grangefertagh was founded in the sixth century AD by Saint Ciarán of Saigir, and known as Fearta-Cáerach ("Sheep's Tomb").

[2] The monastery was reopened by the de Blancheville family for the Canons Regular of St Augustine in the early 13th century.

[3] In 1421 it was so destroyed and desolated that its religious could not 'remain therein, but must wander about and beg their daily bread' [4] but in 1455 it was rebuilt by Thady Megirid/Magriyd, a canon of Inchmacnerin.

A side chapel contains a 16th century[7] tomb said by Carrigan[8] to be that of Seán Mac Giolla Phádraig, King of Osraige.