He was born in Dublin on 9 September 1805, the son of John Freeman-Mitford, 1st Baron Redesdale.
Wellington recommended him to study the private business of the house, so as to qualify himself for the chairmanship of committees, and on the resignation of the Earl of Shaftesbury, 4 February 1851, Redesdale was unanimously chosen his successor, with the approval of Lansdowne, Stanley, and Wellington.