Adam of Bremen’s connection to the missionary activities of his archdiocese and his defence of the primacy of its mission to convert peoples to Christianity, the legatio gentium, has long been identified as the central theme in the Gesta Hammaburgensis. Aage Trommer had already demonstrated in the 1950s the centrality of the legatio in the selection and in the reshaping of Adam’s source material, especially his use of the Vita Anskarii to highlight Hamburg–Bremen’s position in the north. Volker Scior, writing fifty years later, concluded that Adam wrote his chronicle as a response to a crisis, when the rights of the archdiocese over the territories in northern and northeastern Europe were being widely questioned and seemed no more than a vague prerogative. For Scior, it is as a result of such circumstances that Adam set out to write his history of the archbishopric, in the hopes of attracting Liemar’s attention to the legatio gentium. This Adam considered fundamental, not only as a defence of Hamburg–Bremen’s contested position, but also as a statement regarding the importance of the see in a historical–philosophical perspective. Therefore, when reading the Gesta, we need to consider how the text connects and sustains a defence of this legatio in the face of the historical events it narrates. Indeed, a clear understanding of this prerogative was fundamental for the audience for whom Adam wrote, and the fact that he does not spend much time developing the concept may indicate that he assumes his readers are familiar with it.

The legatio gentium is interpreted mainly as a prerogative to Christianize the gentes, that is, the different populations living outside christianitas, the imagined community that unites Christian believers. It is, therefore, no surprise that the legatio has been translated by modern historiography into the concept of mission or missionary activity. However, as Ian Wood recently pointed out, “[m]ission is an early modern concept.” And yet, as Wood also states, “[t]his does not mean that the term would have no relevance to the study of the early Middle Ages, but that the historian should carefully define his area of research.”