[1] Sir John Campbell, of Airds Bay, gained the rank of lieutenant colonel in the service of the Argyllshire and Bute Militia.
He undertook agricultural improvements on the estate, including reclaiming waste land, draining and top dressing.
[2] He was appointed Lieutenant Governor of Saint Vincent and the Grenadines in 1845, in which office he served until his death at Kingstown on 18 January 1853.
At that time, Saint Vincent was a British dominion, having been won from the French at the Treaty of Versailles in 1783 after changing hands more than once during the mid-18th century.
[3] Although Sir John's father, himself, and his son considered themselves rightful heirs to the baronetcy, and used the title socially,[1][3] the Standing Council of the Baronetage later refused to certify their claim.