(1753-26 June 1833), fur trader. (Called Mad McKay). The historian W. S. Wallace thought he was a brother of Alexander and William MacKay, which would have made Donald McKay, the U E Loyalist settler in Charlottenburgh, GC, his father. However, the Dictionary of Canadian Biography does not accept this family connection, which, indeed, is inconsistent with the dates, as we have them, of the two Donalds. In short, so far as is known, Donald Mackay the fur trader has no linkage with Glengarry, other than the possibility that the connection with the U E Loyalist could be correct after all. Donald Mackay the fur trader served with the NWC and (from 1790, and after a period as an independent fur trader) with the HBC. He died in Nova Scotia, where he had settled in 1822. He may have been the brother of the fur trader John McKay.

His life by John C. Jackson in Dictionary of Canadian Biography Vol. VI, also life of John McKay by T. R. McCloy in DCB Vol. V * his life in Wallace and MDict