Robert Bacon (July 5, 1860 – May 29, 1919) was an American statesman and diplomat. He was also a leading banker and businessman who worked closely with Secretary of State Elihu Root, 1905-1909, and served as United States Secretary of State from January to March 1909. He served as ambassador to France 1909 to 1912. He was a leader in the Preparedness Movement setting up training programs for would-be Soldiers before the United States entered the First World War in April 1917. He was defeated narrowly as a candidate for the United States Senate in 1916. He was commissioned as a major in the United States Army in 1917, and played a major role as Chief of the American Military Mission at British General Headquarters.