Gerd Tellenbach (17 September 1903 – 12 June 1999) was a German historian[1] and scholar of medieval social and religious history, particularly of the Papacy and German church during the Investiture Controversy and reform movements of the eleventh and twelfth centuries. Tellenbach also made groundbreaking contributions to the study of the medieval nobility and helped establish a new field of research dedicated to mapping social networks and familial ties among medieval elites (Personenforschung). After studying history at the universities of Freiburg and Heidelberg, he taught in Gießen, Münster, and finally the Albert-Ludwigs-Universität in Freiburg, where he served as Rektor (chancellor) in 1949–1950 and again in 1957–1958. From 1962 to 1971, he was director of the German Historical Institute in Rome, a state-sponsored research center dedicated to German-Italian studies and the history of the Papacy in the Middle Ages.