The American Baptist Churches USA (ABCUSA) is a mainline/evangelical Baptist Christian denomination within the United States. The denomination maintains headquarters in Valley Forge, Pennsylvania. The organization is usually considered mainline, although varying theological and mission emphases may be found among its congregations, including modernist, charismatic and evangelical orientations. It traces its history to the First Baptist Church in America (1638) and the Baptist congregational associations which organized the Triennial Convention in 1814. From 1907 to 1950, it was known as the Northern Baptist Convention, and from 1950 to 1972 as the American Baptist Convention.