(CNN) -- Here's a look at what you need to know about Martin Luther King, Jr. Day a federal holiday that falls on the third Monday in January.
Facts: January 19, 2015 - Martin Luther King, Jr. Day.
King's actual birthday is January 15.
Timeline: April 8, 1968 - Rep. John Conyers (D-MI) introduces legislation for a federal holiday to commemorate King, just four days after his assassination.
January 15, 1969 - The Martin Luther King, Jr. Memorial Center in Atlanta sponsors and observes the first annual celebration of King's birthday.
April 1971 - The Southern Christian Leadership Conference (SCLC) presents to Congress petitions containing three million signatures in support of the holiday. Congress does not act.
1973 - Illinois is the first state to adopt Martin Luther King Jr. Day as a state holiday.
November 4, 1978 - The National Council of Churches urges Congress to enact the holiday.
1979 - Coretta Scott King speaks before Congress and joint hearings of Congress in a campaign to pass a holiday bill. A petition for the bill receives 300,000 signatures, and President Jimmy Carter supports passage of a bill.
November 1979 - The House fails to pass Conyers' King Holiday bill by five votes.
1982 - Coretta Scott King and Stevie Wonder bring the speaker of the House, Tip O'Neil, petitions with over six million signatures in favor of a holiday.
1983 - Congress passes and President Ronald Reagan signs legislation creating Martin Luther King, Jr. Day as a national holiday. Senators Jesse Helms (R-NC) and Gordon Humphrey (R-NH) attempt to block the bill's passing.
January 20, 1986 - First national celebration of the Dr. Martin Luther King, Jr. holiday takes place.
January 16, 1989 - The King holiday is legal in 44 states.
1994 - Coretta Scott King goes before Congress and quotes King from his 1968 sermon, "The Drum Major Instinct," in which he said, "Everybody can be great because everybody can serve." She requests that the holiday be an official national day of humanitarian service.
1994 - Congress designates the holiday as a national day of service through the Martin Luther King, Jr. Federal Holiday and Service Act.
1999 - New Hampshire becomes the last state to adopt a holiday honoring King.
January 17, 2011 - Marks the 25th anniversary of the holiday.