Field Marshal Charles Lennox, 3rd Duke of Richmond, 3rd Duke of Lennox, 3rd Duke of Aubigny, KG, PC, FRS (22 February 1735 – 29 December 1806), styled Earl of March until 1750, of Goodwood House in Sussex and of Richmond House in London, was a British Army officer and politician. He associated with the Rockingham Whigs and rose to hold the post of Southern Secretary for a brief period. He was noteworthy for his support for the colonists during the American Revolutionary War, his support for a policy of concession in Ireland and his advanced views on the issue of parliamentary reform. He went on to be a reforming Master-General of the Ordnance first in the Rockingham ministry and then in the ministry of William Pitt.