Religious leaders have shaped the course of history and deeply affected the lives of many individuals. This book offers alphabetically arranged profiles of roughly 160 religious leaders from around the world and across time, carefully chosen for their impact and importance and to maximize inclusiveness of faiths from around the world. Scholars from around the world, each one an expert in his or her field and all holding advanced degrees, came together to create an essential resource for students and for those with an interest in religion and its history. Not strictly a biographical reference that recounts the facts of religious figures' lives, the book helps users understand how the selected figures changed history. The entries are accompanied by excerpts of primary source documents and suggestions for further reading, while the book closes with a bibliography of essential print and electronic resources for further research.