John Henderson II (1797–1878) was the son of John Henderson (1764–1843) and the amateur artist Georgiana Henderson (1770–1850), daughter of George Keate (1729–97). He devoted his life to the study of archaeology and collecting works of art, many of which, including extensive holdings of the watercolours and drawings of Girtin and Joseph Mallord William Turner (1775–1851), he inherited from his father, who had commissioned them from the young artists. He bequeathed his extensive collections to the University of Oxford, the National Gallery and the British Museum, the last of which received his drawings by Giovanni Antonio Canal (Canaletto) (1697–1768) and John Robert Cozens (1752–97) as well as his watercolours by Girtin and Turner.