Martin Luther King, Jr. Day is a United States holiday marking the birthday of the Reverend Doctor Martin Luther King, Jr. It is observed on the third Monday of January.

Martin Luther King, Jr. was an American clergyman, activist and prominent leader in the African-American civil rights movement. He is referenced as a human rights icon today.

He was the chief spokesman of the nonviolent civil rights movement, which successfully protested racial discrimination in federal and state law.

After King's death, United States Representative John Conyers introduced a bill in Congress to make King's birthday a national holiday.

It is also a national holiday in American Samoa, Guam, US Virgin Islands.