Some of Hollywood’s biggest stars are marking America’s newest national holiday.

On Monday, the U.S. celebrates Juneteenth, a holiday honouring the end of slavery in America after the Civil War in the 1860s.

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Among those celebrating on social media was Lizzo, who for the third straight year id holding a giveaway, including the opportunity for fans to fly out and hang out her her.

In a post on her Instagram Story, she wrote, “Juneteenth is about giving Black citizens of this country our own Declaration of Independence. It is about the complicated and nuanced history we have with this country,” adding, “I hope you’ll use Juneteenth has an opportunity to educate yourself on our history and on how to be anti-racist. Because we ain’t free until we are all free.”

Mariah Carey shared a post on Instagram with her child looking at a photo of her father, Alfred Roy Carey, and a message celebrating both Father’s Day and Juneteenth.

Kerry Washington marked the day by sharing a list of things people can do to honour Juneteenth, including “uplift black voices” and “shop black owned businesses.”

Former U.S. President Barack Obama shared a thread on Twitter, writing, “Today, we remember the struggle for freedom as we reflect on how far we’ve come as a country—and on the work that remains undone.”

READ MORE: Macy Gray Proposes A Redesigned U.S. Flag To ‘Represent All Americans’ In Juneteenth Essay

In a post on her Instagram feed, Tamar Braxton wrote of the holiday, “This day TRULY means.. the land of the free. I give thanks to my ancestors and guides who paved the way for me and my loved ones.”

Juneteenth began as a celebration in the Black community in Texas, making the arrival of Union soldiers in Galveston, who announced the end of the war and that enslaved African-Americans were free.

In recent years, the holiday has become more and more prominent around the U.S., and in 2021, President Joe Biden made it an official federal holiday.