United States Magazine and Democratic Review, est. 1837 · ed. John L. O’Sullivan (1813–1895)
The exact line — “The best government is that which governs least” — first appears as an editorial motto in the debut 1837 issue of the United States Magazine and Democratic Review, the Jacksonian journal founded and edited by John L. O’Sullivan (later famous for coining “Manifest Destiny”). Henry David Thoreau adapted the slightly different phrasing to open Civil Disobedience in 1849, expressly calling it a “motto” he accepted rather than one he invented. Neither Jefferson nor John Locke, to whom it is also sometimes credited, is known to have written it.