But some Americans have, for years, celebrated it as the day that marks our ancestors' emancipation.
June 19, 1865 was the day U.S. Army troops landed in Galveston, Texas. It was the aftermath of the Civil War. The troops informed some of the last enslaved Americans that they were forever free. They enforced President Abraham Lincoln's Emancipation Proclamation, which took effect on January 1, 1863.
The proclamation declared freedom for the slaves of rebels in the South. It came after almost two years of war, and it took more years of war to enforce it. The order did not free every slave, and the document specified places it did not apply.
Frederick Douglass, the activist who'd been enslaved himself, said Lincoln was slow, even "slothful" in making this "obvious" move. But Douglass celebrated that "the dictation of humanity and justice have at last prevailed."