Theodore Roosevelt (1858–1919) was an American statesman, author, explorer, soldier, naturalist, and reformer who served as the 26th President of the United States from 1901 to 1909. Sickly as a child, Roosevelt overcame his health problems by embracing a strenuous lifestyle, becoming a published author, rancher, and Republican mayoral candidate by his late twenties. In the Spanish–American War, Roosevelt rose to national fame through his service with the Rough Riders. In 1898 he was elected governor of New York, and two years later he was made William McKinley's running mate in the election of 1900. When the latter was assassinated in 1901, Roosevelt—then aged 42—became the youngest United States President in history, promoting conservation and expanding the Navy.Photograph: Pach Brothers; restoration: Chris Woodrich