Theodore Roosevelt walking in a homecoming parade with New York City Mayor William Gaynor and Cornelius Vanderbilt, September 14, 1910. Theodore "Teddy" Roosevelt (October 27, 1858 - January 6, 1919) was the 26th President of the United States (1901-1909). He is noted for his exuberant personality, range of interests and achievements, and his leadership of the Progressive Movement, as well as his "cowboy" persona and robust masculinity. He was a leader of the Republican Party and founder of the short-lived Progressive (Bull Moose) Party of 1912. Before becoming President, he held offices at the city, state, and federal levels. Roosevelt's achievements as a naturalist, explorer, hunter, author, and soldier are as much a part of his fame as any office he held as a politician. He was 42 years old when sworn in as President of the United States in 1901, making him the youngest president ever. He was also the first of only three sitting presidents to have won the Nobel Peace Prize. After leaving the White House he led a major expedition to the Amazon jungles but contracted diseases which ruined his health. He died in 1919, at the age of 60, unexpectedly in his sleep from a blood clot. Roosevelt has consistently been ranked by scholars as one of the greatest U.S. Presidents. His notable accomplishments include trust busting and conservationism. His face, alongside three other U.S. presidents, is carved in the granite rock of Mount Rushmore in the Black Hills of South Dakota.