An Act for the Release of Certain Persons from Service or Labor in the District of Columbia (D.C. Emancipation Act), April 16, 1862
The Constitution grants Congress exclusive authority over the District of Columbia. As the Civil War continued, Congress used this power to end slavery in Washington, D.C. On April 16, 1862, President Abraham Lincoln signed an act for the immediate release of the approximately 3,000 enslaved persons in D.C., nine months before the Emancipation Proclamation. The act of Congress also compensated former slaveholders who were loyal to the Union, and created for former slaves a system of voluntary emigration outside the United States. Today, Washington, D.C. celebrates April 16 as Emancipation Day.
General Records of the United States Government, National Archives and Records Administration