It was created, along with the subsidiary title Viscount Brocas, of Southampton in the County of Southampton, on 29 June 1925 for Admiral of the Fleet John Jellicoe, 1st Viscount Jellicoe, on his return from being Governor-General of New Zealand, with remainder to the heirs male of his body.

He had already been created Viscount Jellicoe, of Scapa in the County of Orkney, on 15 January 1918, created with remainder to the heirs male of his body, and in default of such issue to his eldest daughter and the heirs male of her body, with the like remainder in default of such issue to every other daughter successively in order of priority of birth, and to the heirs male of their bodies.

Brocas was chosen due to the descent of Admiral Jellicoe's great-grandmother, Jane Elizabeth, daughter of Sir James Whalley-Smythe-Gardiner, 2nd Baronet, of Roche Court, Fareham, from the last of the Brocases of Beaurepaire (purchased 1353, sold 1873), Sherborne St John, Hampshire.

[4] In 1971, as Lord Brocas, he married Geraldine Ann FitzGerald Jackson; they were divorced in 1981, having one son, Justin Amadeus Jellicoe (born 1970).

[4] As both sons were born outside wedlock, the heir presumptive to the peerages is the present holder's brother, the Hon.