Duncan Campbell (1726-1803), London shipowner in the West India trade, and the man who gave William Bligh his employment between the wars.

The Manx connection is by marriage. Mary, wife of Richard Betham, Collector of Customs at Douglas, was Campbell's sister, so when Bligh married Betham's daughter Elizabeth at Kirk Onchan in 1781 he married into Campbell's family. After the American war many ships were laid off and naval promotion dried up. Bligh, on half pay, commanded ships for Campbell, who already employed two sons of his eldest sister Ann Somerville as captains, and it was that West India experience which made him an obvious choice when the breadfruit expedition was planned.

His other business was convicts. He and his brother Neil had charge of the prison hulks, and he had contracted to carry two hundred and sixty felons to America. American independence ended that trade, and the consequences were laid before the Commons: judges were leaving the gaols as full as they found them, and two hundred persons under sentence of transportation were lying in Newgate alone. The scale of the business survived the loss of the American market. The government's annual budget reported in June 1789 recorded £48,417 paid to Duncan Campbell for convicts.

He came late to planting. He became a Jamaican plantation owner only in 1787, on the estate of his late brother-in-law John Campbell, who died in 1782 and had owned Salt Spring in the parish of Hanover. His ships are reported, on research in the Public Record Office, not to have been in the slave trade, though he was not in favour of the protests against it.