Martin Luther King Jr. Day was founded as a holiday promoted by labor unions in contract negotiations.[2] After King's death in 1968, Rep. John Conyers introduced a bill in Congress to make King's birthday a national holiday, highlighting King's activism on behalf of trade unionists. The King Center turned to support from the corporate community and the general public. The success of this strategy was cemented when musician Stevie Wonder released the single "Happy Birthday" to popularize the campaign in 1980 and hosted the Rally for Peace Press Conference in 1981. Six million signatures were collected for a petition to Congress to pass the law, termed by a 2006 The Nation article as "...the largest petition in favor of an issue in United States History"[3]

At the White House Rose Garden on November 2, 1983, Reagan signed a bill creating a federal holiday to honor King. It was observed for the first time on January 20, 1986.

In May 1990, the holiday was expanded further when President George H. W. Bush signed an extension making the week long celebration into a month-long.

George H. W. Bush signs Martin Luther King Day Proclamation

Reluctance to observe day

Opposition to the bill was led by Senator Jesse Helms, who questioned whether King was important enough to receive such an honor. He was also critical of King's opposition to the Vietnam War, and accused King of having Communist connections.

On January 17, 2000, for the first time, Martin Luther King Day was officially observed in all 50 states.[4] Prior to that New Hampshire and Arizona did not observe the day. Throughout the 1990s this was heavily criticized. After a 1992 proposition to recognize the holiday in Arizona did not pass, the NFL boycotted hosting Super Bowl XXVII at Sun Devil Stadium in Tempe.[5] The hip-hop group Public Enemy recorded a song titled "By The Time I Get To Arizona", on their 1991 album, Apocalypse 91... The Enemy Strikes Black, in which they describe assassinating Arizona Governor Fife Symington III, for his opposition to the holiday.

On May 2, 2000, South Carolina governor Jim Hodges signed a bill to make Martin Luther King Jr.'s birthday an official state holiday. South Carolina is the last state to recognize the day as a paid holiday for all state employees. Prior to this, employees could choose between celebrating Martin Luther King Day or one of three confederate holidays.[6]

While all states now observe the holiday, some did not name the day after King.

In Utah the holiday was known as "Human Rights Day", until the year 2000 when the Utah State Legislature voted to change the name of the holiday from Human Rights Day to Martin Luther King, Jr. Day. In that same year Governor Michael O. Leavitt signed the bill officially naming the holiday "Martin Luther King, Jr. Day."

In Virginia, the holiday was added on to Lee-Jackson Day, a day meant to honor Robert E. Lee and Stonewall Jackson, and became Lee-Jackson-King Day. The incongruous nature of the holiday, which simultaneously celebrated the lives of Confederate Army generals and a civil rights icon, did not escape the notice of Virginia lawmakers. In 2000, a Martin Luther King Day was established in Virginia.

In Arizona and New Hampshire[7], Martin Luther King Day is known as Martin Luther King, Jr. Civil Rights Day.

Although the day is a federal holiday and a state holiday in all states, it is usually not observed by small private companies except for banks. Some large corporations close their operations (more so than on Veterans Day or Columbus Day, which are also federal holidays, but less so than on holidays such as Memorial Day or Labor Day when virtually all corporations are closed), but small shops, restaurants, and grocery stores tend to remain open. Overall, in 2007, 33% of employers gave employees the day off, while 33% of large employers over 1,000 and 32% of smaller employers gave time off. The observance is most popular amongst nonprofit organizations and least popular among factories and manufacturers.[8] The reasons for this have varied, ranging from the recent addition of the holiday (each year more businesses are closed than the year before, though often those that do choose to close "make it up" by no longer closing for Presidents Day) to its occurrence just two weeks after the week between Christmas and New Year's Day, when many businesses are closed for part or sometimes all of the week. Additionally, many schools and places of higher education are closed for classes; others remain open but may hold seminars or celebrations of Dr. King's message.

Service Day

The national Martin Luther King Day of Service was started by former Pennsylvania U.S. Senator Harris Wofford and Atlanta Congressman John Lewis, who co-authored the King Holiday and Service Act. The federal legislation challenges Americans to transform the King Holiday into a day of citizen action through volunteer service in honor of Dr. King. The federal legislation was signed into law by President Bill Clinton on August 23, 1994. Since 1996, the annual Greater Philadelphia King Day of Service has been the largest event in the nation honoring Dr. King.[9] 

Current dates

The United States Code states that MLK day shall be observed on the third Monday in January. In 2008, Martin Luther King Day will fall on January 21, the latest possible date it can fall on.