On this day in 1863,

Lincoln Signs Emancipation Proclamation

Frees Slave in Confederate States Only - None in Union States

On this day in 1862, President Abraham Lincoln used his executive war powers as justification for issuance of the Emancipation Proclamation effective only in the states of the Confederacy and nowhere else in the United States.  The proclamation effectively recast the Civil War as a fight against slavery and discouraged foreign powers from supporting the Confederacy.