1901
- Assumes the Presidency after William McKinley is shot
- Administered the Oath of Office at
Wilcox Mansion near Buffalo, New York
- Invites Booker T. Washington to dine at the White House
- Northern Securities Ltd. incorporated in New Jersey
- Hay-Pauncefote Treaty clears the way for an interoceanic canal
- T.R. appoints Pat Garrett, slayer of Billy the Kid, as Customs Collector of El Paso, Texas
- Isthmian Canal Commission , appointed by President McKinley, recommends Nicaraguan canal route
- Reprimand of Gen. Nelson Miles for criticizing the President's Philippine Independence programme
- Delivers First Annual Message to Congress ; first presidential message to yield paperbound offprints
1902
1903
1904
1905
1906
1907
1908
1909
1910-1911
1912
- Writes "Conservation of Womanhood and Childhood" , the precursor for national legislation protecting women's labor rights and proscribing child labor
- Announces candidacy for the Republican Presidential Nomination; declares himself "Strong as a Bull Moose"
- Progressive Party formed; TR defects from Republican Party; nominated for President by Progressives
- Shot at Milwaukee, Wisconsin, by John Schrank
- Woodrow Wilson defeats Roosevelt and Taft in Presidential election of 1912
- Wins libel suit against George S. Newett
- On her maiden voyage, the Titanic sinks off the coast of Newfoundland; one of the casualties is Archibald Butt, military aide to President Roosevelt
1913
- Leaves for exploration of the River of Doubt in the Amazon
- Federal Reserve System begins operating
- 16th Amendment to the Constitution passed into law; permits collection of personal income taxes
1914 through 1918
- Begins exploration of Rio Duvida in the Amazons; river later renamed Rio Roosevelt
- Panama Canal officially opened
- TR issues statement on Lusitania sinking
- Federal Trade Commission begins operations
- Nominated again for the Progressive Presidential ticket
- Withdraws nomination to support Hughes
- U.S. National Park Service created
- Offers to help in World War I effort by forming Volunteer Division; rebuked by Woodrow Wilson
- President Woodrow Wilson issues his 14 Point plan for a lasting peace; a similar plan for the establishment of an international diplomatic organization was proposed by TR when he was President
1919