He was both prolific and well paid: according to James Boswell, Samuel Johnson spoke of Campbell to Joseph Warton as 'the richest author that ever grazed the common of literature.
In 1734 appeared, under Campbell's name, A View of the Changes to which the Trade of Great Britain to Turkey and Italy will be exposed if Naples and Sicily fall into the hands of the Spaniards.
[2] His first major original work was The Travels and Adventures of Edward Brown, Esq., formerly a merchant in London (1739), fictitious autobiography in the style of Daniel Defoe.
[2] In 1743 appeared anonymously Campbell's English version, with copious annotations, of the Latin work of Johann Heinrich Cohausen, Hermippus Redivivus; or, the Sage's Triumph over Old Age and the Grave.
[2] In 1744 was published Campbell's enlarged edition of John Harris's Collection of Voyages and Travels (1702–05), Navigantium atque Itinerantium Bibliotheca.
[4] To the first Biographia Britannica, the issue of which in weekly numbers began in 1745, Campbell's contributions, signed E. and X., were copious; but they ceased with the publication of vol.
In 1750 there appeared, mainly reprinted from a periodical, 'The Museum,' his work The Political State of Europe, which went through six editions in his lifetime, and gave him a wide reputation.
After the Peace of Paris, 1763, he wrote, at Lord Bute's request, a Description and History of the new Sugar Islands in the West Indies, to show the value of those which had been ceded by the French at the close of the Seven Years' War.
[2] In 1774 appeared his last work, A Political Survey of Great Britain, being a series of reflections on the situation, lands, inhabitants, revenues, colonies, and commerce of the island (2 vols.
Campbell proposed that the state should buy up all the waste lands of the country and develop their latent resources, arable and pastoral.