In the United States, evangelicalism is a movement among Protestant Christians who believe in the necessity of being born again, emphasize the importance of evangelism, and affirm traditional Protestant teachings on the authority as well as the historicity of the Bible. Comprising nearly a quarter of the US population, evangelicals are a diverse group drawn from a variety of denominational backgrounds, including Baptist, Mennonite, Methodist, Pentecostal, Plymouth Brethren, Quaker, Reformed and nondenominational churches.