View images from Theodore (Teddy) Roosevelt's (1858-1919) time as the 26th President of the United States. He entered politics early in life, first as a member of the New York State Assembly before becoming police commissioner of NYC, Assistant Secretary of the Navy, Governor of NYC, and Vice President alongside President William McKinley. McKinley was assassinated six months into his term in 1901, making Teddy the youngest president in American history at the age of 42. He would serve as president from 1901-1909. Roosevelt’s legacy includes breaking up corporate monopolies and land and wildlife conservation.