Juneteenth is Sunday. What's the significance behind the federal holiday?

On Sunday, June 19, Americans will observe the nation's youngest federal holiday – Juneteenth, which became officially recognized last year by President Joe Biden.

Juneteenth came to national prominence in 2020 amid nationwide protests after Minneapolis man George Floyd and Louisville, Kentucky, woman Breonna Taylor were killed during encounters with law enforcement. Both Floyd and Taylor were Black. Their deaths spotlighted ongoing racial inequities in the justice system as well as the legacy of slavery in encounters between Black people and the police.

This month, Alabama Gov. Kay Ivey authorized Juneteenth as a holiday for workers in the state, joining 47 other states that already recognize it as a holiday.

What is the significance of Juneteenth? Here's what we know:

What is Juneteenth?

The holiday commemorates the Emancipation Proclamation in the U.S. President Abraham Lincoln issued the proclamation to free enslaved African Americans in secessionist states on January 1, 1863, but enslaved people in Galveston, Texas, would not learn of their freedom until two years later.

On June 19, 1865, Maj. Gen. Gordon Granger informed the community of Galveston of Lincoln's proclamation. Though it was issued years prior, enslavers were held responsible for telling the enslaved they were free, and some ignored the directive. Maj. Gen. Gordon demanded Galveston locals comply with the proclamation.

Why is it called Juneteenth?

Texas was the last Confederate state where the proclamation was announced, and the first to recognize the date of June 19 – Juneteenth – statewide. The inaugural Juneteenth to commemorate the official day enslaved people in Galveston were freed began in 1866. The holiday, also known as Freedom Day or Emancipation Day, spread across the country as African Americans migrated away from the South.

Why is Juneteenth important?

It is a lesser-known fact that the Emancipation Proclamation did not result in all enslaved African Americans being freed. Juneteenth is part of recognizing the conditions underwent by some Americans unknowingly liberated by law. The proclamation, moreover,guaranteed freedom to enslaved people in secessionist states like Texas, but not Union states like Maryland, which did not secede during the Civil War. The 13th Amendment, ratified in 1865, freed all enslaved people in the country.

When did Juneteenth become a federal holiday?

Congress passed The Juneteenth National Independence Day Act in June 2021, a day after the Senate passed the bill with unanimous consent. Biden signed the bill into law on June 17 – two days before Juneteenth.

The federal government followed the lead of 47 states that already recognized Juneteenth.

Sen. Ed Markey, D-Mass., first introduced the Juneteenth bill in 2020 in the wake of the murders of Floyd and Taylor, but it did not pass.

"Today’s Senate passage of our legislation to commemorate Juneteenth as a federal holiday will address this long-ignored gap in our history, recognize the wrong that was done, acknowledge the pain and suffering of generations of slaves and their descendants, and finally celebrate their freedom," Markey said on June 17 of last year.

Under the act, federal employees are granted a day off on June 19. This year's work reprieve falls on Monday, June 20 because June 19 falls on a Sunday.

Do people celebrate the holiday? Is it OK to say 'Happy Juneteenth'?

Juneteenth is celebrated nationwide with parades, barbecues, competitions for "Miss Juneteenth," rodeos, races and block parties, according to Juneteenth.com, a resource website. A reading of the Emancipation Proclamation is also commonplace.

"Happy Juneteenth Day" is considered an appropriate greeting to mark the occasion, according to the website. The color red is also symbolic. It is featured on the red, white and blue Juneteenth flag and symbolizes that "from the middle passage to George Floyd, our blood has been spilled across America," according to Steve Williams, president of the National Juneteenth Observance Foundation.

The foundation has planned a Juneteenth Freedom Festival to be held June 17-19 in Washington, D.C.

Reach out to Chelsey Cox on Twitter at @therealco.

This article originally appeared on USA TODAY: Juneteenth is a US federal holiday: Here's why June 19 is important