After the death of Louise de Kérouaille, Duchess of Portsmouth (c. 19 August 1673 - 14 November 1734), it was created in 1743 for John Wallop, 1st Viscount Lymington, who had previously represented Hampshire in the House of Commons.
The earls were in possession of a large trove of Newton's personal papers, until they were auctioned in 1936.
The fifth Earl resumed, without Royal licence, the family surname and arms of Wallop.
Oliver Henry Wallop, the eighth Earl, had moved from England to the United States, and been living the life of a rancher in Sheridan, Wyoming, at the time of the death of his older brother, the seventh Earl.
The heir apparent is the present holder's son Oliver Henry Rufus Wallop, Viscount Lymington (b.