What is Juneteenth in the USA?

Juneteenth, also known as Freedom Day or Emancipation Day, is the oldest known celebration commemorating the ending of slavery in the United States.
President Lincoln’s Emancipation Proclamation was effective Jan. 1, 1863, but the news took time to travel. It wasn’t until June 19, 1865, when the Union army brought word of the proclamation to enslaved people in Galveston, Texas, making them among the last to be freed.
The celebration of June 19 came to be known as “Juneteenth” and grew with more participation from descendants as they treated the day as their Independence Day, according to the Texas State Library. It spread to other states and has been celebrated every year since.