Ever since the publication of Jaeger’s Envy of Angels, scholars have increasingly replaced the emphasis on schools with a focus on schoolmasters. Scholars like Münster-Swendsen and Steckel have explored intellectual culture and in doing so have formulated theories about the relationship between masters and students and on the importance of a schoolmaster’s reputation. Still, a glaring gap remains in the historiography concerning the lack of studies examining the schoolmaster’s social reality and his everyday life. Moreover, scholarly attention has been spread unevenly over various regions and chronological periods. Generally speaking, the Carolingian period and the twelfth century have receive the lion’s share of scholars attention at the expense of the eleventh century. Similarly, imperial schools and famous educational centres in France such as Chartres, Laon and -above all- Paris have been at the forefront of scholar’s efforts. Within this historiographical landscape my thesis seeks to remedy these gaps by pursuing a study of eleventh-century schoolmasters in dioceses in Normandy and the Southern Low Countries. In doing so the purpose of this thesis is twofold. The first aim is prosopographical, given that this thesis examines the careers of cathedral schoolmasters active in these dioceses so as to understand the educational developments happening there. Secondly, my thesis hopes to offer a social history of schoolmasters in the eleventh century. Underlaying this is a desire to understand the transformation of education in central medieval Europe. By comparing the educational developments in Normandy and the Southern Low Countries, I contend that something new can be said about the way in which cathedral schools were set up in Western Europe. In the end I hope to be able to explain why some schools and schoolmasters became hugely successful, while others did not and to provide an eleventh-century context and background to the changes in education in the twelfth century. To achieve these goals, this thesis is divided into two parts. Part I takes a prosopographical approach to the dioceses of Arras, Cambrai, Liège, Thérouanne and Tournai in the Southern Low Countries and Avranches, Bayeux, Coutances, Évreux, Lisieux, Rouen, and Sées in Normandy. Part II takes a thematical approach by using the schoolmasters that were studied in part I as cases to explore topics such finance, career patterns, education, rivalry, school types, and the relationship between bishop and schoolmaster. The immediate contribution of Part I is that it provides an examination of the careers of forty-eight schoolmasters by interpreting primary sources, comparing careers, and providing context. As a result I have highlighted the careers of lesser known, largely unnoticed schoolmasters next to more famous teachers like Odo of Tournai. Much of this work is new, while some of it expands on previous work or corrects previous views. Along the same lines, I have studied cathedral schools that thus far have received very little scholarly attention such as Arras and Thérouanne or Coutances and Avranches. The result is a better understanding of the educational development in the regions under consideration. The schoolmaster that arises from part II remains somewhat of an elusive figure. On some matters I have been able to successfully sketch the characteristics of schoolmasters as a social group, while for other matters this has proven more difficult decades of the eleventh century. Still, the majority of my findings are new and cannot be found in the work of scholars such as Lesne or Barrow. It will suffice here to highlight some of the more striking conclusions. I have recognized three groups of schoolmasters: the first group, by far the largest, remained teachers at one place throughout their careers, the second group remained teachers, but taught at more than one place, and the final group consists of teachers who enjoyed a wider career within the Church. This last group could follow two possible career paths: a secretarial one as chancellor or a managerial one as dean or archdeacon. Despite earlier studies that claimed that schoolmasters in the eleventh century were mobile from quite early on, I have concluded that this was not the case. Instead schoolmasters often came from inside the cathedral chapter after having been a student at the cathedral school where they themselves would teach. This also means that the wandering schoolmaster is a trademark of the twelfth century that started to occur more frequently during the last competing schoolmasters in the eleventh century, but these are rare. Again we see an increase as the eleventh century progressed. As for the underlying question of the way in which cathedral schools were set up, I have singled out the important role of bishops who took the initiative by making funds available and by appointing a schoolmaster from outside the diocese. As the school became more ingrained schoolmasters tended to come from the inside and the cathedral chapter became more involved. Most cathedral schools catered to an essentially local student audience, although scholars have long recognised that some schools enjoyed wider success for a short while. This success has been ascribed to the schoolmaster’s reputation. In essence, this is true, but on the basis of my case studies I have proposed a model to explain the success of schools by looking at both structural and incidental factors. Structural factors were long-term and formed the foundation on which the cathedral school was build such as political stability, urban peace,religious uniformity, and a stable student audience. Incidental factors were short-term and the most important ones were episcopal support for a school and the success and reputation of the schoolmaster. Drawing on incidental factors we can explain the short-lived success of cathedral schools such as Tournai which for a brief period of time became European wide centres of education. After the schoolmaster disappeared, the success of the school waned away as well. This contrasts with the sustained success of the Liègeois cathedral school throughout the eleventh century which was built on structural factors. There the identity of the schoolmaster was of lesser importance.