At the height of the tumultuous developments taking place in Central and Eastern Europe in the ninth century, two Greek missionaries from Thessalonica came to the fore. Their work of acculturation among the Slavs had far-reaching and lasting changes upon European life. This book looks back over the life and work of these two outstanding figures and analyzes their ecclesiastical and cultural mission. Their presence in the Crimea was closely bound up with several aspects of Byzantium's ecclesiastical policy and programs of acculturation, and also with the Russians' first encounter with Christianity. In presenting the Slavs with an alphabet and the written word, the brothers transmitted to them the world, and this it was in Cyril and Methodius' time, and thanks to their work, that Great Moravia reached the height of its vigor and prosperity as a central European state. The Cyrillo-Methodian tradition lived on, spreading among the Slavic peoples and laying the foundation of their spiritual life.