President John Tyler was otherwise known as “His Accidency” because he took office when President William Henry Harrison died after only 31 days in office. It is presumed Tyler died from a stroke.

Side note: After Tyler’s wife died in the White House, he became the first president to marry while in office and he married a woman 30 years his junior. His new wife at 21 years old (Tyler was 54) became the youngest first lady in history. Tyler had eight children by his first wife, and seven by his second.