It is often thought that linguistics has to be very technical and complicated (it doesn't), as well as boring (it needn't be). In fact, linguistics can often finesse hard information out of historical documents in a manner that is just as striking and revealing-and just as scientific and objective-as the way in which archaeology helps us to interpret historical artefacts. The process involves looking beyond what is expressed in such a document to the question of how it is expressed; this exposition looks in simple terms at some specific examples that relate to early medieval Ireland, Britain and the Continent.

This deliberately informal exposition originated in a 2012 address given at NUI Galway in response to an invitation from the students of that university's Cumann Staire. A version was delivered the following year in Dublin to a workshop of the Royal Society of Antiquaries of Ireland. It is essential reading for any student of history.