Washington's will freed 123 people, his heir sold 54 more, and the family sold Mount Vernon for $200,000

In 1799, 317 enslaved people lived at Mount Vernon. George Washington owned 124 of them and leased 40. The other 153 were Custis dower slaves he could not legally free. His July 1799 will freed his valet, William Lee, at once. The rest were left to Martha for her life and were to be freed at her death. The estate had to support the old and sick, and children were to be taught to read and freed at 25. Martha freed them on 1 January 1801. She died on 22 May 1802. Most of the dower slaves then passed to her grandson George Washington Parke Custis, the builder of Arlington. Washington's nephew Bushrod Washington inherited Mount Vernon. In 1821 he sold 54 enslaved people to Louisiana plantations for $10,000. Hezekiah Niles questioned the sale in his Weekly Register. In 1853 John Augustine Washington III offered the estate to Virginia, which said the price was too high, and to the federal government, which declined. On 6 April 1858 he agreed to sell the mansion and 202 acres to the Mount Vernon Ladies' Association for $200,000. The association took possession on 22 February 1860. In 2026 the association still owns and runs Mount Vernon^†.