The initial call for a holiday in honor of the civil rights leader came from union leaders as a part of contract negotiations, though Representative John Conyers first introduced a bill in Congress to make the leader's birthday a national holiday shortly after King's death in 1968.
The bill would likely have died in Congress were it not for the persistence of the King Center and union members in various industries across the country, who advocated strongly for the holiday. Many unions also held strikes until provisions were including in their contracts that stipulated King's birthday would be a paid day off, according to The Nation.
When Conyers' bill, which he reintroduced in Congress numerous times, did come up for a vote in the House in 1979, it fell five votes short of passing, despite then-President Jimmy Carter's endorsement. Opponents argued that awarding the day off would be costly, and that a federal holiday honoring a private citizen was contrary to tradition.
Since 1968, the King Center had been calling upon supporters, policy officials, union leaders and corporations to back workers taking the day off, eventually launching a campaign to generate public support for MLK Day that resulted in Stevie Wonder dedicating his hit song "Happy Birthday" to King in 1980. That led to large donations from corporations like Coca-Cola and Miller Brewing Company in 1982.
The final push came when the King Center collected 6 million signatures in favor of an MLK Day bill, "the largest petition in favor of an issue in U.S. history," according to The Nation.
All of these efforts led up to Nov. 2, 1983, when then-President Ronald Reagan signed a bill creating a federal holiday in King's honor. Though Reagan had originally opposed the holiday for cost reasons, it passed in the House with a veto-proof margin.
Martin Luther King Jr. Day was then finally observed as a national holiday for the first time on Jan. 20, 1986.
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