John Boit Jr (15 October 1774 – 8 March 1829) was one of the first Americans involved in the maritime fur trade. He sailed as fifth mate under Captain Robert Gray on the second voyage of the Columbia Rediviva, 1790–1793. During the voyage he wrote a short but important journal in which he described the discovery of the Columbia River. John Boit was born on 15 October 1774 to John and Sarah Brown Boit, both of Boston.