Conrad Johan (John) Immanuel Bergendoff (December 3, 1895 –December 23, 1997) was an American Lutheran theologian and historian. He served as the fifth president of Augustana College in Rock Island, Illinois from 1935 to 1962.
Conrad Bergendoff was born in Shickley, Nebraska, to Carl August and Emma Mathilda Fahlberg Bergendoff. He spent his youth in Middletown, Connecticut. He graduated from Augustana College, Rock Island, Illinois in 1915 and earned his M.A. at the University of Pennsylvania in 1916. He returned to Rock Island to complete the B. Div. degree at the [Augustana Theological Seminary. Bergendoff was ordained into the ministry of the Augustana Lutheran Synod on June 12, 1921 in Chicago. He pursued advanced study at Sweden's Uppsala University, serving as personal secretary to Swedish Archbishop Nathan Söderblom during the Stockholm Conference on Life and Work in 1925. He earned his Ph.D. from the University of Chicago in 1928.
Bergendoff became dean of the Augustana Theological Seminary in 1931, and was elected to succeed Gustav Andreen as president of Augustana College in 1935. He saw the college through the difficult years of the Great Depression, through its separation from Augustana Theological Seminary in 1948, and into a long period of substantial growth and increasing prestige.
Among his most notable achievements was the ecumenical spirit he engendered in American Lutherans from the late 1930s going forward. Instrumental in gathering together the myriad branches of the European immigrant Lutheran bodies, Bergendoff used his considerable influence and power within the Augustana Synod to help unite those Swedish-background churches into the United Lutheran Church in America (1962-1987), a precursor of the current Evangelical Lutheran Church in America. Bergendoff also devoted considerable attention to the ecumenical movement between major Protestant denominations, and on a more local and regional level he made many inroads towards official cooperation with leaders of conservative and reformed movements in American Judaism.