John Henry Upton succeeded his father as 2nd Baron Templetown in 1785. He was created Viscount on 13 February 1806. On 7 October 1796, he had married Lady Mary Montagu [d. 1824], daughter of the 5th Earl of Sandwich. They had four sons and a daughter, of whom sons Henry Montagu and George Frederick became 2nd and 3rd Viscounts, respectively.