Stanton, Edwin McMasters, 1814–69, American statesman, b. Steubenville, Ohio. He was admitted to the Ohio bar in 1836 and began to practice law in Cadiz. As his reputation grew, he moved first to Steubenville (1839), then to Pittsburgh (1847), and finally to Washington, D.C. (1856), becoming ever more prominent in his profession. In Dec., 1860, Stanton, a Democrat but a strong Unionist, succeeded Jeremiah S. Black as U.S. Attorney General in President Buchanan's cabinet. Later, he became legal adviser to Abraham Lincoln's Secretary of War, Simon Cameron. Appointed to take Cameron's place in Jan., 1862, he proved to be an extremely forceful and able Secretary of War. Contracts ceased to be opportunities for graft; the railroads were placed under military control; and Union generals in the field were supplied with necessary men and matériel. One of the leading radicals in the Lincoln administration, Stanton worked closely with the radicals in Congress and used his influence with Lincoln to advance their program. Deeply grieved by Lincoln's death, he arranged for a swift trial of the alleged conspirators by a military court. Stanton remained in President Andrew Johnson's cabinet, but serious differences over Reconstruction policy led Johnson to demand (Aug., 1867) his resignation. When he refused to resign, Johnson suspended him, first appointing Ulysses S. Grant as secretary ad interim and then appointing Lorenzo Thomas as permanent Secretary of War. Stanton, however, barricaded himself in his office, and the radicals in Congress, claiming that Johnson's actions violated the Tenure of Office Act, initiated impeachment proceedings against him. When Johnson was acquitted (May, 1868), Stanton resigned. He died shortly after President Grant appointed him to the U.S. Supreme Court.
See biographies by F. Pratt (1953, repr. 1970) and B. P. Thomas and H. M. Hyman (1962); study by R. G. Mangrum (1980).