William Scarlett was born in Columbus, Ohio, on October 3, 1883. He graduated from Harvard University in 1905 and enrolled at the Episcopal Theological School in Cambridge, Massachusetts, receiving his Bachelor of Divinity degree in 1909. In 1911, he was called to Trinity Cathedral in Phoenix, Arizona, where he served as dean for eleven years. In 1922, Scarlett began his service as dean of Christ Cathedral in St. Louis, Missouri. He held the position until his election as Bishop Coadjutor of Missouri eight years later. He was elected Bishop of Missouri in 1933, serving until 1952.

As Bishop of Missouri, Scarlett committed the resources of the diocese to helping those left jobless and homeless by the Great Depression. In 1935, the Episcopal City Mission was created to minister to those in the city’s jails. He also revitalized Christian education in the congregations, recognizing that the future of The Episcopal Church was at stake.

Known as a liberal clergyman, Scarlett championed the idea of church unity and wanted cooperation among all denominations. He was one of the founders of the St. Louis Chapter of the Conference of Christians and Jews and was invited to share ownership of St. Luke’s Hospital with the Presbyterians. As president of the Urban League of St. Louis for sixteen years, he sought to make his community aware of problems in race relations. While on the national board of the Urban League and American Civil Liberties Union, Scarlett advocated for the equal rights for people of color long before the issue was addressed by the institutional church.

His personal papers are located at The Archives of the Episcopal Church.