The S in Harry S Truman’s name did not stand for anything. It was meant as a tribute to both of Truman’s grandfathers, both of whom had middle names starting with S.

Before he became an actor (and long before he worked in politics) Ronald Reagan worked as a lifeguard. 

President Grover Cleveland once worked as a hangman.

When he took office in 1901, Theodore Roosevelt was the youngest person ever elected president at the age of 42.

William McKinley was once portrayed on an American $500 bill, but the McKinley bill was discontinued in 1969.

In 1910, William Howard Taft became the first sitting president to throw the opening ceremonial pitch at a Major League Baseball game.

Woodrow Wilson had just two years political experience as governor of New Jersey before he was elected president in 1912.