Baron Cullen of Ashbourne, of Roehampton in the County of Surrey, is a title in the Peerage of the United Kingdom. It was created on 21 April 1920 for Sir Brien Cokayne, Governor of the Bank of England from 1918 to 1920. As of 2017[update] the title is held by his grandson, the fourth Baron, who succeeded his uncle in 2016.
The first Baron was the son of George Cokayne, Clarenceux King of Arms and editor of the first edition of The Complete Peerage, son of the Hon. Mary Anne Cokayne, granddaughter of Charles Cokayne, 5th Viscount Cullen.