This study examines the evolution of the image of Aleksandr Nevskiy in close connection with the dynamics of the political and cultural history of medieval Russia. It demonstrates that historians often misinterpret the Life of Aleksandr Nevskiy and treat it as a source for political and military history. By putting the Life in the context of Christian (not only Orthodox) culture, the study achieves remarkable and impressive results in its analysis of the Life. With its mature and innovative methodology it also demonstrates how the Life impacted on common historical consciousness, as it was placed into the historical framework of the medieval Russian chronicles. This researches places Isoaho among those scholars of medieval Russian history, who study the role of political leaders in the formation of the Russian state.