In 1906, William J. Seymour (1870-1922) preached Pentecostal revival at the Azusa Street mission in Los Angeles. From these and other humble origins the movement has blossomed to 631 million people around the world. Gastón Espinosa provides new insight into the life and ministry of Seymour, the Azusa Street revival, and Seymour's influence on global Pentecostal origins. After defining key terms and concepts, he surveys the changing interpretations of Seymour over the past 100 years, critically engages them in a biography, and then provides an unparalleled collection of primary sources, all in a single volume. He pays particular attention to race relations, Seymour's paradigmatic global influence from 1906 to 1912, and the break between Seymour and Charles Parham, another founder of Pentecostalism. Espinosa's fragmentation thesis argues that the Pentecostal propensity to invoke direct unmediated experiences with the Holy Spirit empowers ordinary people to break the bottle of denominationalism and to rapidly indigenize and spread their message. The 104 primary sources include all of Seymour's extant writings in full and without alteration and some of Parham's theological, social, and racial writings, which help explain why the two parted company. To capture the revival's diversity and global influence, this book includes Black, Latino, Swedish, and Irish testimonies, along with those of missionaries and leaders who spread Seymour's vision of Pentecostalism globally.