Juneteenth, also known as Freedom Day or Emancipation Day, is a holiday in the United States honoring African American heritage by commemorating the announcement of the abolition of slavery in the U.S. State of Texas in 1865. Celebrated on June 19, the term is a portmanteau of June and nineteenth, and is recognized as a state holiday in 36 states of the United States.
The holiday originated in Galveston, Texas; for more than a century, the state of Texas was the primary home of Juneteenth celebrations, and since 1980, Juneteenth has been an official state holiday in Texas. It is considered a "partial staffing holiday", meaning that state offices do not close, but some employees will be using a floating holiday to take the day off. Its informal observance has spread to some other states, with a few celebrations even taking place in other countries.
As of March 2010, 36 states and the District of Columbia have recognized Juneteenth as either a state holiday or state holiday observance; these are Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Florida, Idaho, Indiana, Illinois, Iowa, Kansas, Kentucky, Louisiana, Massachusetts, Michigan, Minnesota, Missouri, Nebraska, New Jersey, New Mexico, New York, North Carolina, Ohio, Oklahoma, Oregon, South Carolina, Tennessee, Texas, Vermont, Virginia, Washington, West Virginia, Wisconsin and Wyoming. In some areas, however (particularly those with their own emancipation dates), there is resistance to celebrating what is, in essence, a Texas holiday.
Though Abraham Lincoln issued the Emancipation Proclamation on September 22, 1862, with an effective date of January 1, 1863, it had minimal immediate effect on most slaves’ day-to-day lives, particularly in Texas. Texas was resistant to the Emancipation Proclamation, and though slavery was very prevalent in East Texas, it was not as common in the Western areas of Texas, particularly the Hill Country, where most German-Americans were opposed to the practice. Juneteenth commemorates June 18 and 19, 1865. June 18 is the day Union General Gordon Granger and 2,000 federal troops arrived in Galveston, Texas, to take possession of the state and enforce the emancipation of its slaves. On June 19, 1865, legend has it while standing on the balcony of Galveston’s Ashton Villa, Granger read the contents of “General Order No. 3”:
That day has since become known as Juneteenth, a name derived from a portmanteau of the words June and nineteenth.
Former slaves in Galveston rejoiced in the streets with jubilant celebrations. Juneteenth celebrations began in Texas the following year. Across many parts of Texas, freed people pooled their funds to purchase land specifically for their communities’ increasingly large Juneteenth gatherings — including Houston’s Emancipation Park, Mexia’s Booker T. Washington Park, and Emancipation Park in Austin.
This information is courtesy of wikipedia