In 1846, Tappan was among the founders of the American Missionary Association (AMA), led by Congregational and Presbyterian ministers, both white and black. It linked anti-slavery activists of the East with Ohio and other Midwestern activists. In addition, it took over managing numerous disparate missions: an Oberlin, Ohio mission to the Red Lake-area Ojibwe, a mission to Jamaica, a Mende mission to the "Amistad" Africans, and a mission to escaped blacks living in Canada. As the AMA grew in influence, it expanded its enterprises. Among these, it began 115 anti-slavery Congregational churches in Illinois, aided by anti-slavery ministers such as Owen Lovejoy there.