Influenced by a second law partner, Judge (and later Senator) Benjamin Tappan, Stanton became a Democrat and entered politics. Stanton won election in 1837 as Harrison County’s prosecuting attorney, then served as the Ohio Supreme Court’s recorder from 1842 to 1845. Although active in the local antislavery society, he continued to support the Democrat party because of its stance on other issues. Throughout most of the 1840s and 1850s, though, he concentrated on his law practice, not on politics. He became friends with the U.S. attorney general under President James Buchanan (1857-1861), Jeremiah Black, who appointed Stanton to investigate land fraud in California for the federal government. In 1859 he served as one of the lead attorneys on the defense team of Congressman Daniel Sickles, who stood accused of murdering his wife’s lover. Stanton and his colleagues convinced the jury to acquit Sickles on the grounds of temporary insanity, marking one of the earliest uses of that plea.

In the 1860 presidential election, Stanton, like Buchanan and Black, supported the Southern Democratic nominee, John C. Breckinridge, as the best hope for preserving the Union. In December, following the election, the lame-duck President Buchanan reorganized his cabinet, moving Black to the state department. Stanton replaced his friend as attorney general and worked diligently to keep the Union intact, urging the outgoing president to take a firm stance against secession and for federal control of Southern forts. His advice to Buchanan went unheeded, so Stanton began secretly working with the Republicans, passing information to Senator William Seward and others concerning the administration’s deliberations.

In March 1861 Stanton returned to his Washington D.C. law practice, which included giving occasional counsel to President Lincoln’s secretary of war, Simon Cameron. In December of that year Cameron accepted Stanton’s suggestion to strengthen the passage in the secretary’s annual report that endorsed the use of black troops in the Union military. When Cameron resigned his post in January 1862 under a cloud of corruption and mismanagement charges, Lincoln named Stanton to replace him. In so doing, the president appears to have acted on the advice of Seward, now secretary of state, and Salmon Chase, secretary of the treasury.

Stanton proved to be a strong, effective cabinet officer, a talented war manager, and a reformer who instituted practices to rid the War Department of waste and corruption. By working closely with both Republican and Democratic congressmen, he was better able to secure passage of military bills. He enthusiastically endorsed emancipation of the slaves and confiscation of rebel property. The secretary of war was one of the key voices encouraging the president to remove General George McClellan, a former friend, from his position as commanding general of the Union army. Stanton played a crucial role in selecting commanders, superintending military operations, and developing strategy, particularly toward a more aggressive policy.

The most controversial aspect of Stanton’s job was as head of internal security. At first he limited the use of martial law, but reversed that position in the wake of resistance to the draft and emancipation. Thereafter he more freely suspended the writ of habeas corpus and authorized extensive military arrests. He exercised strict censorship over war information through control of the military telegraph system. In March 1863 Congress created in essence a temporary national police force (Provost Marshal General’s Bureau) directed by the secretary of war, which Stanton used to crack down on anti-draft and anti-war dissenters.

Stanton switched allegiance in mid-war from the "War" Democrats to the Republican party, the latter of which he had come to identify with the preservation of the Union. During the 1864 election he generously offered furloughs to servicemen so that they could return home to vote, assuming correctly that they would cast their ballots overwhelmingly for Lincoln’s reelection. When Supreme Court Chief Justice Roger Taney died in October 1864, Stanton desired appointment to the post. Lincoln, however, concluded that he was more important to the Union cause as secretary of war, so the president named Chase, instead. Upon the assassination of Lincoln, Stanton is said to have uttered the memorable line, "Now he belongs to the ages."

Stanton continued to serve as President Andrew Johnson’s secretary of war and initially backed the new president’s reconstruction plan. He became distressed, though, over reports of anti-black violence and resistance to federal control, especially via lawsuits against army officers. Stanton stayed in the cabinet to provide a voice for tougher reconstruction policies, and he worked with General Grant behind the scenes to shift military loyalty from the president to Congress. In March 1867 Congress passed, over Johnson’s veto, the Tenure of Office Act which forbade a president from removing a Senate-confirmed appointee without the Senate’s express approval. The law was enacted in large part to protect Stanton, who was increasingly earning the president’s ire. The secretary of war himself drafted the Chain of Command Act of 1867 which legally forced the president to issue military orders through the commanding general (Grant). The statute was an attempt to stop Johnson from thwarting the military-enforced reconstruction policies of Congress.

Stanton supported the Reconstruction Acts of 1867, which implemented Congressional Reconstruction, and he and Grant authored the third such law, placing military control clearly under Congress rather than the president. That was the final straw for Johnson, who demanded Stanton’s resignation. After the secretary of war refused, the president suspended him in August 1867, naming Grant as acting secretary. When Congress reconvened in January 1868, the Senate judged that Johnson’s action had violated the Tenure of Office Act, so they restored Stanton to office. The next month the president again attempted to remove Stanton, this time replacing him with General Lorenzo Thomas as acting secretary. With Congressional support, Stanton refused to leave office, claiming job protection under the Tenure of Office Act. Congress simply ignored Johnson’s pronouncement and, instead, voted to impeach the president. Meanwhile, Stanton had literally locked himself in the War Department until the Senate voted on the President’s removal, which was narrowly defeated. Disappointed, Stanton resigned on May 26 and was replaced by General John Schofield.

In retirement Stanton’s chronic asthma left him a semi-invalid, financially dependent on friends. His wish to sit on the Supreme Court appeared to be fulfilled when President Grant appointed him to a vacancy and the Senate confirmed him on the same day, December 20, 1869. He died, however, four days later in Washington, D. C, before taking his seat.

Sources consulted: American National Biography; Harper’s Encyclopedia of United States History; The Complete Book of the U.S. Presidents; Harper’s Weekly; and Lydia L. Rapoza, "Edwin Stanton," on the Revolution to Reconstruction Website.