Many people assume that slavery ended with the Emancipation Proclamation, but the last slaves in the United States weren't freed until nearly three years later, on June 19, 1865, otherwise known as "Juneteenth." It is also known as Juneteenth Independence Day, Freedom Day and Emancipation Day.
It is important to remember that while the Emancipation Proclamation, issued on January 1, 1863, technically freed the slaves, it didn't apply to states that had seceded from the Union during the Civil War. Many of the southern states still practiced slavery, and many people were enslaved for years after the Emancipation Proclamation.
On June 19, 1865 - two months after the end of the Civil War - General Gordon Granger rode to Galveston, Texas with 2,000 Union troops to read General Order No. 3, which freed 250,000 slaves. Thus began the traditional celebration of Juneteenth, but it wasn't all singing and dancing from the outset.
Many former slaves were intimidated and discouraged from celebrating. Some even continued to work for their former owners. Segregation in certain states barred African-Americans from using public spaces for their celebrations. And because of Jim Crow laws and the Great Depression, African-Americans were migrating towards northern cities to find work. There, it was nearly impossible to take the day off to celebrate - especially since it hadn't yet been recognized as an official holiday.
Towards the end of the 20th century and through 2015, a strong movement has revived Juneteenth as both a day of celebration and of national awareness. In 1979, Texas was the first state to make Junteenth an official holiday. As of 2015, it is officially recognized by 43 states.