In 1876, President Ulysses S. Grant appointed Cameron to his cabinet as Secretary of War, a post his father once served in during the Lincoln administration, to succeed Alphonso Taft, who became Attorney General, and served as so until the end of Grant's presidency. Cameron's predecessor, Alphonso Taft, had initially replaced William W. Belknap, who had abruptly resigned over taking profit payments from the Fort Sill tradership. The Secretary of War had been given control over all Indian traderships in 1870. Belknap was impeached by the House, and during the summer of 1876 was tried and acquitted by the Senate. Cameron's appointment as Secretary of War was part of a sensational three move realignment by President Grant. U.S. Attorney General Edwards Pierrepont was appointed Minister to England; Secretary Taft was appointed U.S. Attorney General; and Cameron was appointed Secretary of War, on the advice of his father, Senator Simon Cameron. Cameron had never served political office until appointed Secretary of War. Cameron had to quickly acquaint himself with the War Department that was in the midst of fighting the Great Sioux War. After the controversial 1876 Presidential election, Cameron had to contend with the Southern States who threatened to secede from the United States a second time. According to General of the Army William T. Sherman, the U.S. military during 1876 was as active as it had been since the Civil War.