What is sometimes called classical Pentecostalism grew out of the late 19th-century Holiness Movement in the United States. The Holiness preacher Charles Fox Parham began preaching (1901) to his Topeka congregation that speaking in tongues was objective evidence of baptism in the Spirit. After Parham's Los Angeles–based Apostolic Faith mission became the center of a great revival (1906), the movement quickly spread around the world. Over the next two decades the movement split along doctrinal and racial lines. Of the many Pentecostalist denominations in the United States today, the largest are the Church of God in Christ, with about 5.5 million members (2000); the Assemblies of God, with about 2.5 million members (2000); the Pentecostal Assemblies of the World, with about 1.5 million members (2000); and the Church of God (Cleveland, Tenn.), with about 870,000 members (2000).