He has been listed as the owner of the Plaisance Estate plantation, in Grenada, by Legacies of British Slave Ownership. However, he cannot have been owner of the Plaisance Estate at the time the claim for compensation for 124 enslaved of £3140 was successfully contested by the mortgagee Archibald Paull over the owners John Henry Earle Berkely and Thomas Berkeley whose claim was unsuccessful. So if he did own the Plaisance Estate and not just a house and grounds by that name as referred to in his will, Ref: 1857 Macdonald, John Barkly, Wills and Testaments Ref. SC8/35/8 Sherriff's Court, Rothesay, it can only have been after the abolition of slavery in the British Empire (came into effect August 1, 1834) as he is not listed as an owner before that. John Barkly Macdonald is listed as having been awarded compensation for two enslaved people in Grenada and a group of 27 in Trinidad, however, the latter was in payment to him as a mortgage holder and not as the owner of the slaves. Legacies of British Slave Ownership http://www.ucl.ac.uk/lbs/person/view/41969.
