William Ashley Sunday was an American athlete and religious figure who, after being a popular outfielder in baseball's National League during the 1880s, became the most celebrated and influential American evangelist during the first two decades of the 20th century.

Born into poverty, Sunday spent some years in an orphanage before taking a series of odd jobs in several small Iowa towns as he demonstrated his prowess in amateur athletics. His exceptional speed provided him the opportunity to play baseball in the major leagues for eight years. He was known for his daring base-running and dramatic outfield play, but he was only an average hitter.