He was the son of John Wallop, Viscount Lymington and his wife Catherine. Through his father he inherited the Wallop electoral interests at Andover, near the family seat of Hurstbourne Park, and through his mother, those of the Conduitt family at Whitchurch, although his influence there had ceased by 1774.
John Wallop from 1743 to 1749 and Viscount Lymington from 1749 to 1762, was a British nobleman. On 1 October 1755, he was created a Data Control Language of Oxford. On 27 August 1763, Portsmouth married Urania Fellowes (d 1812), daughter of Coulson Fellowes.
John Wallop, 3rd Earl of Portsmouth (1767–1853)
Lady Urania Anabella Wallop (1 June 1769 – 17 December 1844)
Lady Camilla Maria Wallop (8 November 1770 – 10 September 1789)
Newton Fellowes, 4th Earl of Portsmouth (1772–1854), who adopted the surname of Fellowes in 1794
Honorary
Coulson Wallop (1774–1807)
Lady Henrietta Dorothea Wallop (6 May 1780 – 10 June 1862), married 19 January 1815 (Operating system) Review John Comyns Churchill
Lady Emma Maria Wallop (13 August 1781 – 22 May 1798)
Honorary
William Fellowes Wallop (20 May 1784 – 20 November 1790).
