Theodore Roosevelt Jr.[b] (October 27, 1858 - January 6, 1919), often referred to as Teddy or by his initials, T. R., was an American politician, statesman, conservationist, naturalist, and writer who served as the 26th president of the United States from 1901 to 1909. He previously held various positions in New York politics, rising up the ranks to serve as the state's 33rd governor for two years. He later served as the 25th vice president under president William McKinley for six months in 1901, assuming the presidency after McKinley's assassination. As president, Roosevelt emerged as a leader of the Republican Party and became a driving force for anti-trust and Progressive policies.A sickly child with debilitating asthma, Roosevelt overcame his health problems by embracing a strenuous lifestyle. He integrated his exuberant personality and a vast range of interests and achievements into a "cowboy" persona defined by robust masculinity. He was home-schooled and began a lifelong naturalist avocation before attending Harvard College. His book The Naval War of 1812 (1882) established his reputation as a learned historian and popular writer. Upon entering politics, Roosevelt became the leader of the reform faction of Republicans in New York's state legislature. His first wife and mother died on the same night, devastating him psychologically. He recuperated by buying and operating a cattle ranch in the Dakotas. Roosevelt served as assistant secretary of the Navy under President McKinley, and in 1898 helped plan the highly successful naval war against Spain. He resigned to help form and lead the Rough Riders, a unit that fought the Spanish Army in Cuba to great publicity. Returning a war hero, Roosevelt was elected New York's governor in 1898. The New York state party leadership disliked his ambitious agenda and convinced McKinley to choose him as his running mate in the 1900 presidential election, in which Roosevelt campaigned vigorously and the McKinley-Roosevelt ticket won a landslide victory based on a platform of victory, peace, and prosperity.