Theodore Roosevelt Jr. 1858 – 1919, American statesman, author, explorer, soldier, naturalist, and reformer who served as the 26th president of the United States. He was also Assistant Secretary of the Navy before joining the Rough Riders, where he became famous for courage during the Spanish-American War. He was elected governor of New York and became the 25th Vice President under William McKinley, promoting a platform of peace, prosperity and conservatism. McKinley was assassinated and Roosevelt became, at age 42, the youngest American President in history. As a leader of the Republican Party, he was a driving force for the Progressive Era in the early 20th century. In 1906 he was awarded the Nobel Peace Prize and history still considers him one of the greatest American presidents.
Here is a signed letter on White House stationary by Theodore Roosevelt