[Svartalfiar]

Missouri, West Virginia, and Maryland had ended slavery on their own before the end of the rebellion. When the 13th Amendment was ratified only Kentucky and Delaware has slaves left to free.

Where did you get that? I'm not doing deep research, but even Wikipedia mentions:

Legally, the last 40,000-45,000 slaves were freed in the last two slave states of Kentucky and Delaware[179] by the final ratification of the Thirteenth Amendment to the Constitution on December 18, 1865. Slaves still held in Tennessee, Kentucky, Kansas, New Jersey, Delaware, West Virginia, Maryland, Missouri, Washington, D.C., and twelve parishes of Louisiana[180] also became legally free on this date.

[DoodleDawg]

Where did you get that? I'm not doing deep research, but even Wikipedia mentions...

Well since you're a fan of Wikipedia, History of Slavery in Missouri gives January 11, 1865 for the date slavery ended in that state. History of Slavery in Maryland gives November 1864 for when slavery ended in that state. History of Slavery in West Virginia gives February 1865 for when slavery was ended in that state. Slavery in Kansas Territory says slavery was ended there in 1860. Washington D.C. Emancipation Act ended slavery in D.C. in 1862. History of Slavery in Louisiana says slavery was ended there by the state constitution of 1864. Andrew Johnson and Emancipation in Tennessee says the slaves in that state were freed by proclamation in October 1864.