This psalter was made in Ireland (Armagh?), probably in the late 12th century to judge from the style of the script. The scribe signed his name on one of its pages: 'Cormacus wrote this psalter: pray for him'. Its decoration shares some features of manuscripts from Armagh, but it combines stylistic elements seen in 8th- and 9th-century illumination (in masterpieces such as the Book of Kells) with current styles. Containing canticles or verse passages from the Bible, such as Deut. 32:1-43, as well as the Book of Psalms, it was used as a prayerbook or hymnal in church services. This page presents a prayer asking forgiveness for sin and an introductory prayer of supplication to God found in many early Psalters. The prayer is laid out in geometric panels, a graphic format for prayers which can be seen in much earlier manuscripts. The sparse decoration, consisting of interlaced animals up and down the sides of the frame, is a late version of styles of the 7th and 8th centuries, indicating how long-lived 'Celtic' art, which began in the Iron Age, could be. The colours, too, are much the same as earlier palettes, and the very fine drawing resembles that in an important early 9th-century manuscript made at Armagh, the Book of Armagh, now in Trinity College Library, Dublin.