The Book of Deer (Evangelia) is a Gospel Book written in a hand that was current in the period c. 850-1000 and generally dated to the first half of the tenth century. While the manuscripts to which the Book of Deer is closest in character are all Irish, scholars have tended to argue for a Scottish origin, and it is widely regarded as the earliest manuscript produced in Scotland. Of the four Gospels only the text of St John is complete. Each Gospel is prefaced by a full-page illumination (1v, 16v, 29v, 41v). The manuscript belongs to the category of 'Irish pocket Gospel Books', produced for private use rather than for church services.
The association with Deer is deduced from additions in Gaelic or Middle Irish (3-5) including an account of the foundation of a monastery by Saint Columba and Saint Drostan and land grants to the house, and a Latin brieve of King David I in favour of the 'clerics of Deer' (40). One entry is dated 8 David I (1131-32). It is reasonable to assume that the manuscript was at Deer in Aberdeenshire when these additions were made.