Washington - The United States marked the end of slavery by celebrating Juneteenth on Friday, with the annual unofficial holiday taking on renewed significance as millions of Americans confront the nation’s living legacy of racial injustice.

Demonstrations, prayers and cultural celebrations of food and music will enliven communities from New York to Los Angeles to honor the day in 1865 when a Union general proclaimed in Galveston, Texas that all slaves were free.

Several commemorations have gone virtual to account for the coronavirus pandemic, but many are going ahead as planned or with modifications such as social distancing and mask-wearing guidelines.

Early Friday, several streets in downtown Washington were closed to traffic and there was a strong police presence in the new “Black Lives Matter” plaza near the White House, where protesters were to converge in the afternoon.

Some 155 years after the demise of the pro-slavery Confederacy, several tragedies have led the country into a reckoning on race.

They have also energized a quest for equality among African Americans who decry how systemic racism and injustice have been allowed to fester in the world’s flagship democracy. Forty-six-year-old African-American George Floyd was killed on May 25 when a white Minneapolis police officer pressed his knee onto Floyd’s neck for nearly nine minutes and ignored multiple pleas of “I can’t breathe.”

Video of the horrific incident triggered coast-to-coast protests against racial injustice and police brutality. Millions took to the streets under the “Black Lives Matter” banner.

Further fuelling tensions, an officer in Atlanta last week shot dead a black man who was running away after a scuffle with police.

Both offending officers in the incidents have been charged with murder, and the killings have spurred US lawmakers to introduce sweeping new police reforms.

As Americans grapple with their country’s legacy, Juneteenth has the potential to amplify calls for action and reform.

Protests are scheduled in cities like Tulsa, Oklahoma, which hosts a day-long “I, Too, Am America” rally for justice.

US President Donald Trump used incendiary language to level criticism at protesters following Floyd’s death, and he added fuel to the fire when he scheduled a huge campaign rally on Juneteenth in Tulsa, his first since the pandemic began.

Trump faced an outcry over his provocative choice of date and location -- Tulsa suffered one of the country’s worst racist massacres, in 1921, when as many as 300 black Americans were killed -- and he changed the rally to Saturday.

Dozens of events Friday throughout New York will mark the holiday, including a march to City Hall demanding “justice, dignity and equality” for black Americans.