Henry L. Stimson, American colonel, lawyer, and politician, 46th United States Secretary of State (d. 1950)

Henry Lewis Stimson (September 21, 1867 – October 20, 1950) was an American statesman, lawyer, and Republican Party politician. Over his long career, he emerged as a leading figure in U.S. foreign policy by serving in both Republican and Democratic administrations. He served as Secretary of War (1911–1913) under President William Howard Taft, Secretary of State (1929–1933) under President Herbert Hoover, and Secretary of War (1940–1945) under Presidents Franklin D. Roosevelt and Harry S. Truman.

The son of the surgeon Lewis Atterbury Stimson, Stimson became a Wall Street lawyer after he had graduated from Harvard Law School. He served as a United States Attorney under President Theodore Roosevelt and prosecuted several antitrust cases. After he was defeated in the 1910 New York gubernatorial election, Stimson served as Secretary of War under Taft. He continued the reorganization of the United States Army that had begun under his mentor, Elihu Root. After the outbreak of World War I, Stimson became part of the Preparedness Movement. He served as an artillery officer in France after the United States entered the war. From 1927 to 1929, he served as Governor-General of the Philippines under President Calvin Coolidge.

In 1929, President Hoover appointed Stimson as Secretary of State. Stimson sought to avoid a worldwide naval race and thus helped negotiate the London Naval Treaty. He protested the Japanese invasion of Manchuria, which instituted the Stimson Doctrine of nonrecognition of international territorial changes that are executed by force. After World War II broke out in Europe, Stimson accepted President Franklin Roosevelt's appointment to the position as Secretary of War. After the United States entered World War II, Stimson took charge of raising and training 13 million soldiers and airmen, supervised the spending of a third of the nation's GDP on the Army and the Air Forces, helped formulate military strategy, and oversaw the Manhattan Project to build the first atomic bombs. He supported the atomic bombings of Hiroshima and Nagasaki.

During and after the war, Stimson strongly opposed the Morgenthau Plan, which would have deindustrialized and partitioned Germany into several smaller states. He also insisted on judicial proceedings against Nazi war criminals, which led to the Nuremberg trials.

Stimson retired from office in September 1945 and died in 1950.