In the Emancipation Proclamation, Lincoln does not mention Delaware, Kentucky, Maryland, and Missouri. These states had slaves but were not part of the Confederacy. What happens to the slaves in these states?
The states named were able to keep their slaves much longer than those who were members of the Confederacy. Maryland and Missouri abolished slavery before the Civil War's end, but Delaware and Kentucky remained slave states up until December of 1865, when the Thirteenth Amendment was ratified.