The Episcopal Diocese of Duluth was a diocese of the Episcopal Church in the United States of America. The diocese was created as the Missionary District of Duluth in 1895 as a result of the division of the Diocese of Minnesota. The Missionary District was reconstituted as a diocese at its twelfth annual convocation on June 19, 1907. The diocese reunited with the Diocese of Minnesota in 1944. The former cathedral in Duluth was sold to a Lutheran church in 1956.