“A common misconception is that Juneteenth marks the end of slavery in the United States. Although this day marks the emancipation of all slaves in the Confederacy, the institution of slavery was still legal and existed in two Union border states after June 19, 1865.
“Slavery in the United States did not officially end until the ratification of the Thirteenth Amendment to the Constitution of the United States on December 6, 1865, which abolished non-penal slavery in all of the U.S. states and territories”
“When the Thirteenth Amendment became operational, the scope of Lincoln’s 1863 Emancipation Proclamation was widened to include the entire nation. Although the majority of Kentucky’s slaves had been emancipated, 65,000–100,000 people remained to be legally freed when the amendment went into effect on December 18. In Delaware, where a large number of slaves had escaped during the war, nine hundred people became legally free.”
Actually it lasted in Indian Territory until 1866, when new treaties were entered into with the Indian tribes (who were slaveholders) to abolish slavery. Those tribes fought with the Confederacy during the war, although some like the Cherokee eventually split into slave-owning and abolitionist factions.
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