On April 16th, 1862 President of the United States of America Abraham Lincoln signed the Compensated Emancipation Act. This act freed the the slaves of the District of Columbia as well as compensating the former owners with approximately $300 ($6,846.53 according to The Inflation Calculator) per slave. This was the only time that owners where compensated by the federal government and came nine months prior to the better known Emancipation Proclamation.
Emancipation Day was celebrated from 1866 to 1901 originally. Because of the hard work of Loretta Carter Hanes the day started to be celebrated again in 2002 and then in 2005 was made a public holiday in the District of Columbia.
It is celebrated by parades and demonstrations as well as school programs to help educate the school children.