During the late 1920s and 1930s, Leighton visited the United States on a number of lecture tours, emigrating to the US in 1939. In 1930, the Art Institute of Chicago awarded her with the Mr. And Mrs. Frank G. Logan First Prize ($100). She lived in Baltimore for a while and became friends with H. L. Mencken. Leighton became a naturalized citizen in 1945. From 1943 to 1945 she was a member of the Department of Art, Aesthetics, and Music at Duke University. In 1945 she was elected into the National Academy of Design as an Associate member and became a full Academician in 1949.