A charter is basically a legal document, issued by kings, ecclesiastics or laymen, written on parchment, perhaps sheep or goat skin, in either French, Gaelic or Latin (also Scots from the late fourteenth century). Charters could record a number of different things, such as a grant of lands in return for military service, a resignation of lands in favour of a third party, a forfeiture of lands, or a confirmation of lands or privileges. These were important documents and both secular (like earls, lords and barons) and ecclesiastic (like bishops and abbots) landowners owned charter rooms and charter chests. If a landowner lost a charter he could not legally prove that he held title to the land in question, unless there was a copy in the governmental chancery. It has been suggested that to begin with, during the eleventh and early twelfth centuries, the charter was a document which conveyed information and recorded a grant or privilege. It did not physically constitute a grant but preserved a record of a ceremony (possibly a perambulation, where the boundary markers of an estate were either fixed or examined to check that they had not been altered) which had already occurred.

The earliest surviving Scottish charter has been dated to 1094 AD and records (in Latin) a grant to the church of Durham by Donnchad mac Máel Coluim (Duncan II). During this early period, writing would have been the preserve of a very small body of people, essentially churchmen, and it is probable that the king’s personal chaplains would have written royal charters until clerks first appear in the late twelfth century. Charters always conclude with a witness list: a selective list of names of people who were present when the grant was made and who could bear witness to it. The final act was the authentication of the document, achieved by attaching the donor’s seal to the charter. Witness lists are of great importance to historians. They can provide names and titles of people not known from other evidence and, as the names are listed in order of importance, a witness list shows exactly where a certain person was ranked in society at a particular point in time. For example, in the charter of David mac Máel Coluim (David I) in the Book of Deer, the name of Gregory, bishop of Dunkeld, appears first among the ecclesiastic witnesses. He would have been the senior bishop present. Likewise, because the name of Donnchad, earl of Fife, appears first among the secular witnesses, he would have been the senior earl present.

However, charters are also very important to historians for other reasons. Often, they preserve early forms of place-names and some charters contain records of the boundary markers by which lands were perambulated. Information of this nature allows a historian to trace the exact extent of a particular estate. Charters can also tell us why lands were taken away from one individual and given to another, or what an individual had to do in return for being given a grant of land. Often, this took the form of some kind of military service: knight, archer or boat.

In the case of the Latin charter in the Book of Deer, it is impossible to decide why the grant was copied into the book. One possible explanation might be that although a judgement had been made in their favour, the community had not yet received their charter from David mac Máel Coluim’s chancery and were making their own record of the outcome. Equally, the charter may have been copied into the book as a safeguard in case the original charter was lost or destroyed.