Traitors, every one of them. And I’d add southern aristocrats who helped fund the war to the list of people who should have been on the gallows.

He didn't own them. He managed them as one of the executors of the Custis estates. By the terms of the Custis will. the slaves had to be freed within five years of Custis's death, or sooner once the debts and legacies of the estate were paid.