Pentecostal (Pentecostalism) denomination established by Aimee Semple McPherson (McPherson, Aimee Semple), a popular revivalist preacher, in Los Angeles in 1927. During a revival campaign in Oakland, California, U.S., four years earlier, “Sister” Aimee claimed to have seen a vision of four living creatures reminiscent of the one recorded in the Old Testament book of Ezekiel (1:5–10). She interpreted the faces of these four creatures—a lion, a man, an ox, and an eagle—as symbolizing perfection, and she equated a perfect, foursquare, full gospel with one that would stress four themes: salvation, Holy Spirit baptism, healing, and the Second Coming of Christ. These four themes became the hallmark of her preaching, and in a short time hundreds flocked to her meetings; in two years she was able to dedicate Angelus Temple in Los Angeles as the “mother church” of the Foursquare Gospel Association. From 1923 the organization grew to national and international importance.

Branch churches sprang up in the environs of Los Angeles; by 1925, 32 had been established in southern California, and 50 more were appealing to Angelus Temple for permission to affiliate. By the late 20th century the Foursquare Gospel Church had become one of the largest Pentecostal denominations.

The episcopal character of its church government bears the stamp of the founder, around whom everything centred during her lifetime. McPherson was president of the church and the ruling power and voice of the organization. She held the power of veto; she appointed all officers; she hired all personnel and set their salaries. Her son and successor, Rolf K. McPherson, carried on this tradition. Doctrinally, however, the church is similar to the Assemblies of God, on whose ministerial rolls Aimee Semple McPherson's name appeared for several years during her early evangelistic career.

In 1997 the group reported 231,522 members and 1,832 congregations in the United States. Headquarters are in Los Angeles. A related group, the Foursquare Gospel Church of Canada, reported 3,063 members and 54 congregations in 1996; its headquarters are in Surrey, British Columbia.