When Washington took over Mount Vernon at age 22 there were 18 slaves.
When he married he gained control of 200 more which technically belonged to the estate of his wife’s first husband. By 1786 he owned 216 slaves. (Flexner,p114)
1766: Washington sent a “rogue and runaway” slave to the islands to be sold for rum, molasses, etc. (Flexner,p114)
1774: Washington said new British laws would make Americans "as tame and abject slaves as the blacks we rule over with such arbitrary sway." (Flexner, p114)
1778/9: Washington was reluctant to buy or sell slaves, although he felt that: “If these poor wretches are to be held in a state of slavery, I do not see that a change of masters will render it more irksome, provided husband and wife, and parents are not separated from each other, which is not my intention to do." (Flexner, p118)
1786 Washington complained about a Quaker abolitionist society: “I can only say that no man living wishes more sincerely than I do to see the abolition of (slavery)…But when slaves who are happy & content to remain with their present masters, are tampered with & seduced to leave them… it introduces more evils than it can cure."(Hirschfield,p187)
Before 1793: "The unfortunate condition of the people whose labors I in part employed has been the only unavoidable subject of regret. To make the adults among them as easy and comfortable as their actual state of ignorance and improvidence would admit; and to lay a foundation to prepare the rising generation for a destiny different from that in which they were born, afforded some satisfaction to my mind, and could not, I hoped, be displeasing to the justice of the Creator." (Flexner, p121)
1793: As president Washington signed the Fugitive Slave Act.
1793: Washington hoped to rent and/or sell parts of his land, freeing the slaves to work as laborers. In a private letter he said his most powerful motive was:"to liberate a certain species of property which I possess very repugnantly to my own feelings, but which imperious necessity compels, and until I can substitute some other expedient by which expenses not in my power to avoid (however well disposed I may be to do it) can be defrayed." He was unable to find suitable renters or buyers and the plan fell through.(Flexner, p113)
Approx 1794: One of Washington’s slaves died: “I hope every necessary care and attention was afforded him. I expect little from (Overseer) McKoy, or indeed from most of his class, for they seem to consider a Negro much in the same light as they do the brute beasts on the farms, and often treat them as inhumanely.” (Wilkins,p83)
While Washington was serving as president in Philadelphia a Pennsylvania law was passed freeing slaves whose owners had been citizens of the state for six months. Washington sent his two most valuable slaves home, telling them it was for his wife’s convenience.(Wilkins, p76)
In 1796 Oney (or Ona) Judge ran away to New Hampshire.She was one of Washington’s slaves - Martha’s personal servant. President Washington asked the Treasury Secretary for help in getting her back: “I am sorry to give you, or any one else trouble on such a trifling occasion, but the ingratitude of the girl, who was brought up and treated more like a child than a Servant (and Mrs Washington’s desire to recover her) ought not to escape with impunity if it can be avoided.”(Wilkins,p82. Also: Gerson.)
1796: A federal customs official in New Hampshire located Washington’s runaway slave Oney Judge.Washington asked him to “seize her and put her on board a Vessel bound immediately to this place or to Alexandria (Virginia).” The customs official warned that this would spark a riot.(Gerson )
The customs official wrote that Oney Judge agreed to return if Washington promised to free her in his will. Washington wrote to the customs official:“I regret that the attempt you made to restore the Girl (Oney Judge as she called herself while with us, and who without the least provocation absconded from her Mistress) should have been attended with so little Success. To enter into such a compromise with her as she suggested to you is totally inadmissible, for reasons that must strike at first view: for however well disposed I might be to gradual abolition, or even to an entire emancipation of that description of People (if the latter was in itself practicable at this moment) it would neither be political or just to reward unfaithfulness with a premature preference; and thereby discontent before hand the minds of all her fellow-servants who by their steady attachments are far more deserving of favor.” Oney Judge remained free. (Wilkins,p82)
When Washington left the presidency he apparently left some house slaves behind in Philadelphia, knowing that under state law they would be quietly freed by having spent a certain amount of time in Pennsylvania. (Flexner)
1799. Washington complained that he had too many slaves. "To sell the overplus I cannot, because I am principled against this kind of traffic in the human species. TO hire them out is almost as bad, because they could not be disposed of in familes to any advantage, and to disperse the families I have an aversion. What then is to be done? Something must or I am ruined..." (Hirschfield p. 74)
When he died in 1799 his will called for his manservant William Lee to be freed immediately, and given a pension. The other slaves were to be freed when his widow died. Martha chose to free them two years later. According to Abigail Adams this was because MW feared her life might be in danger, since her death meant freedom for the slaves. (Hirschfield p 214)
Neither Washington nor Martha could legally free the dower slaves which she had inherited from her first husband, except by purchasing them from the estate. They did not do so.