WASHINGTON (CNN) – Tuesday is the 150th anniversary of the signing of the Emancipation Proclamation.
The proclamation, signed by President Abraham Lincoln on January 1, 1863, freed slaves in Confederate states
To honor of the milestone, the US Postal Service unveiled a new stamp commemorating the document at the National Archives in Washington on New Year's Day.
The stamp, which is being issued as a "forever" stamp, features some famous words from the document.
