Gerald Christian Wimsey, 4th Duke of Denver of the second creation, generally referred to as the 16th Duke, is the elder brother of Lord Peter Wimsey in the books by Dorothy L. Sayers. He is a major figure in the novel Clouds of Witness, and in the sub-plot of The Attenbury Emeralds by Jill Paton Walsh. He married his second cousin Helen and had two children, Gerald "Jerry" Wimsey, courtesy Viscount St. George (who died in the Second World War) and Lady Winifred Wimsey (not in the line of succession to the family titles).
The Duke was the son of Mortimer Gerald Wimsey, 15th Duke of Denver and Honoria Lucasta Delagardie, both of whom Philip José Farmer has found (in his book Tarzan Alive) to descend from witnesses to the Wold Newton Meteorite strike.