1887: The U.S. Senate approved an agreement to lease Pearl Harbor in Hawaii as a naval base.

1937: Franklin D. Roosevelt became the first U.S. president sworn into office in January. It was his second of four inaugurations.

1961: John F. Kennedy was sworn in as the 35th president of the United States.

1981: Ronald Reagan was sworn in as the 40th president of the United States.

1981:Iran released 52 Americans held hostage for 444 days, minutes after the presidency had passed from Jimmy Carter to Ronald Reagan.

1986: The United States observed the first federal holiday in honor of slain civil rights leader Martin Luther King Jr.

1989: George H.W. Bush was sworn in as the 41st president of the United States.

1991: Bill Clinton was sworn in as the 42nd president of the United States.

2001: George W. Bush was sworn in as the 43rd president of the United States.

Do you have suggestions for additions to this date? If so, please write and say so - let's make this the most informative calendar possible!