Did the Trans-Atlantic slave trade continue all the way up to 1865, or was there an earlier point at which US slavery became "self-sustaining?"
The last shipment of slaves to the United States was in autumn of 1859 by the schooner "Clotilde" to Mobile, Alabama. The act of bringing enslaved Africans to the United States was illegal by this time, so the Clotilde was burned and scuttled (deliberately sunk) soon after the Federal authorities found out.