(WASHINGTON) — President Joe Biden is set to sign a bill Thursday afternoon making Juneteenth a federal holiday commemorating the end of slavery in the United States — just in time for Saturday’s June 19 anniversary.

It’s a day African Americans have celebrated each year since the Civil War-era and the culmination of a decades-long effort by advocates to get national recognition for the momentous development in American history.

The federal government said most employees will be off this Friday to mark the occasion, around which celebrations have become more mainstream in recent years, taking on added significance last year when the country went through a racial reckoning after the killing of George Floyd.

Vice President Kamala Harris, the nation’s first Black vice president, a co-sponsor of the legislation when she served in the Senate, will speak about the significance of the moment at a White House signing ceremony.

Earlier Thursday, House Speaker Nancy Pelosi and Democrats with the Congressional Black Caucus held bill enrollment ceremony to highlight the victory.

“This is an important step for America,” she said.

The group on Capitol Hill sang the hymn “Lift Every Voice and Sing,” what’s called the Black National Anthem, in unison, to close the ceremony.

Advocates say Juneteenth — also known as Freedom Day, Liberation Day and Emancipation Day — offers a day to reflect on the terrible stain on American history and celebrations look similar those on the Fourth of July.

It’s celebrated on June 19 to mark the day in 1865 when African American slaves in Galveston, Texas, were among the last to be told they had been freed — a full two-and-a-half years after the Emancipation Proclamation and two months after the Civil War officially ended.

Though advocates have worked for decades to make Juneteenth a national holiday, even succeeding at the state level everywhere but South Dakota, it took Congress only two days to pass the legislation once one Republican senator, Sen. Ron Johnson, who blocked the move last year, dropped his opposition.

The bill then passed the Senate by unanimous consent on Wednesday before passing the House Thursday night in a 415-14 vote, with all opposition coming from GOP members.

Juneteenth is the first new holiday created by Congress in nearly 40 years, when lawmakers in 1983 designated Martin Luther King Jr. Day as the third Monday in January to memorialize the assassinated civil rights leader.

Ahead of Biden’s signing, the U.S. Office of Personnel Management said on Twitter that “most federal employees will observe the holiday tomorrow, June 18th” since it falls on a weekend.

Amid high tensions, former President Donald Trump was forced to reschedule a campaign rally in Tulsa, Oklahoma, on June 19, 2020, after he was criticized as culturally insensitive for scheduling the riot on the holiday and near the forgotten Tulsa Race Massacre. Trump said he moved the rally, “out of respect” for the occasion.

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