This Wednesday is the third annual Juneteenth observance in the United States, a federal holiday honoring the liberation of Black slaves at the close of the Civil War in 1865.

The origin of the holiday’s name dates back to June 19, 1865, when U.S. Army Major General Gordon Granger entered Galveston, Texas, and declared to an estimated 250,000 slaves that they were now free following four years of fighting between the Confederate states in the south and the victorious Union army of the United States north.

Granger’s order carried out the Emancipation Proclamation, which was signed on January 1, 1863, by then-President Abraham Lincoln and released over 3 million Black slaves across the Confederacy. However, the Emancipation Proclamation did not go into effect until the Confederacy submitted at the end of the war.

Communities of color observed the day.