American Baptist Churches USA traces its organizational life to 1814, when Baptists across the young United States formed the Triennial Convention, a national missionary cooperative meeting once every three years. The Convention held for three decades until slavery split it. In 1845, after the American Baptist Home Mission Society refused to commission a missionary who owned slaves, Baptist churches across the South withdrew and formed the Southern Baptist Convention. The mission and publication societies that remained kept operating independently across the North and West for another six decades, without a single unified national body of their own.
That changed on May 17, 1907, when delegates meeting in Washington, D.C., reorganized the Triennial Convention's surviving societies into the Northern Baptist Convention, electing the future Supreme Court justice Charles Evans Hughes as its first president. The name held until 1950, when the Convention became the American Baptist Convention, acknowledging that its member churches were never confined to the northern states the old name implied. A second and final renaming followed in 1972, to American Baptist Churches USA, the name the denomination carries today. William R. Hutchison's 1989 history counts it among the Seven Sisters of American Protestantism, the tradition's most institutionally prominent members through the middle of the twentieth century, alongside the Episcopal Church, the Evangelical Lutheran Church in America and four others already living in this atlas.