Gesta Hammaburgensis ecclesiae pontificum

Adam of Bremen's history of the see of Hamburg and of Christian missions in northern Europe from the late eighth to the late eleventh century is the primary source of our knowledge of the history, geography, and ethnography of the Scandinavian and Baltic regions and their peoples before the thirteenth century. Arriving in Bremen in 1066 and soon falling under the tutelage of Archbishop Adalbert, who figures prominently in the narrative, Adam recorded the centuries-long campaign by his church to convert Slavic and Scandinavian peoples. His History vividly reflects the firsthand accounts he received from travelers, traders, and missionaries on the peripheries of medieval Europe.