Harry Hines Woodring was an American politician. A Democrat, he was the 25th Governor of Kansas and the United States Assistant Secretary of War from 1933 to 1936. His most important role was Secretary of War in President Franklin Delano Roosevelt's cabinet from 1936 to 1940. After 1938, Roosevelt rejected isolationism regarding Europe. Woodring quietly opposed Roosevelt and was eventually fired.

The secretary of war was a member of the U.S. president's Cabinet, beginning with George Washington's administration. A similar position, called either "Secretary at War" or "Secretary of War", had been appointed to serve the Congress of the Confederation under the Articles of Confederation between 1781 and 1789. Benjamin Lincoln and later Henry Knox held the position. When Washington was inaugurated as the first President under the Constitution, he appointed Knox to continue serving as Secretary of War.