The Faddan More Psalter was discovered during peat cutting in a Tipperary bog in 2006.

The book fell open upon discovery, and the visible Latin words in ualle lacrimarum (in the valley of tears) identified it as a psalter. The Psalter or Book of Psalms is a section of the Old Testament Bible. Biblical texts were first brought to Ireland during the 5th century by Christian missionaries. As Christianity spread, these texts were copied by Irish scribes. The Psalter came to hold a central place in the Irish monastic system, and children learned to read and write from the Psalter before being handed over to the monks for further instruction. Monks were expected to know the psalms from memory.

The Faddan More Psalter was probably written around AD 800, in a nearby monastery, copied from an existing psalter. The dense network of monastic sites in this rich and fertile area close to the River Shannon provides a number of possibilities. Scribes are known to have worked at Lorrha, Birr and Terryglass, all of which are reasonably close to Faddan More. A holy well named the Brandy Well, located on an island in the bog, may refer to St. Brendan, founder of the monastery of nearby Birr.

Excavation of the find place showed that the Psalter had been deposited along with a pigskin bag and an animal pelt. Radiocarbon dates from the other material found on the excavation indicate that the artefacts were deposited within a few hundred years of the Psalter being written, before AD 1000. The reasons for the deposition are not known. Earlier peat cutting in the bog uncovered an ancient wooden vessel and a fine leather satchel that dates to between the 7th and 9th centuries AD.