Aimee Semple McPherson (Aimée, in the original French; October 9, 1890 - September 27, 1944), also known as Sister Aimee or simply Sister, was a Canadian-American Pentecostal evangelist and media celebrity in the 1920s and 1930s, famous for founding the Foursquare Church. McPherson has been noted as a pioneer in the use of modern media, because she used radio to draw on the growing appeal of popular entertainment in North America and incorporated other forms into her weekly sermons at Angelus Temple, one of the first megachurches.
In her time she was the most publicized Protestant evangelist, surpassing Billy Sunday and her other predecessors. She conducted public faith healing demonstrations before large crowds; testimonies conveyed tens of thousands of people healed. McPherson's articulation of the United States as a nation founded and sustained by divine inspiration continues to be echoed by many pastors in churches today.
News coverage sensationalized her misfortunes with family and church members; particularly inflaming accusations she had fabricated her reported kidnapping, turning it into a national spectacle. McPherson's preaching style, extensive charity work and ecumenical contributions were a major influence to Charismatic Christianity in the 20th century.