Study of insular history of the period between the Viking era and the twelfth century has been revitalized by focus on the inter-relationships of the peoples of the Irish Sea region. Is it possible to recover something of the contemporary perceptions of these inter-relationships? What was the perception of the relationship between the Irish and their kinsmen overseas, the descendants of those who had settled in various parts of Britain from around the late Roman period? By the tenth century, Irish settlements in Wales were a distant memory, their legacy surviving only in placenames, inscriptions and anecdote. Yet an active link had been maintained over about four centuries between the homeland and the descendants of Irish settlers in the northwest of Britain, a link mediated through shared language, custom and ecclesiastical association. As the period between the tenth and twelfth centuries was marked by considerable political and social change on both sides of the Irish Sea, how was the relationship between the ‘sea-divided Gaels’ of Ireland and of Scotland in that era configured by Irish literati?

In assembling the evidence I have drawn not only on sources conventionally regarded as historical documentation, such as the Irish annals, genealogical collections and synchronisms of reigns, but also on other vernacular texts, hitherto classed as ‘literary’, and therefore largely unexploited for their historical testimony.