A friend of Abraham Lincoln and future father-in-law of Robert Todd Lincoln, James Harlan had left his Iowa U.S. Senate seat when appointed as Secretary of the Interior under President Andrew Johnson in May 1865. He had a sixteen month often controversial tenure, during which he famously dismissed Walt Whitman on moral grounds after reading in Leaves of Grass. Increasingly out of tune with Johnson's reconstruction policies, he resigned and was immediately returned to the U.S. Senate by the Iowa legislature. He was succeeded in the cabinet by another Republican, and friend of Lincoln, Orville Browning of Illinois. (By John Osborne)
"United States," The American Cyclopedia and Register of Important Events of the Year 1866 (New York: D. Appleton and Company, 1873), 756.