Klaus Wetzel provides a comprehensive and detailed account of the history of the global spread of Christianity in this work, organized chronologically from the expansion of Christianity in the first six centuries in Asia, Europe, and Africa, through the missions in the Middle Ages and the spread of Christianity from the 16th to the 18th century—with initial approaches to Protestant world missions—up to the global missions from the 19th to the 21st century. He addresses missiological questions where they historically arose and explores the motivations for mission and conversion, as well as the significance of contextualization and transformation processes. In a concluding chapter, he poses the question of a possible theological interpretation and significance of history. Only those who know the history of missions can understand the great developments.