Duke of Denver

The fictitious title of Duke of Denver was created by Dorothy Sayers for the family of Lord Peter Wimsey. Lord Peter is the second of the three children of Mortimer Wimsey, 15th Duke of Denver. Gerald Wimsey, 16th Duke of Denver, and Peter's elder brother, is the chief murder suspect in Clouds of Witness, in which he is tried by his peers, in full form in the House of Lords.

C. W. Scott-Giles, Fitzalan Pursuivant of Arms Extraordinary, discussed the family with Miss Sayers from February 1936 until 1940, and they discovered many former Wimseys in their correspondence. These came in two types:

A biographical note, supposedly by his uncle Paul Austin Delagardie, says:

Miss Sayers published several articles and pamphlets on the Wimseys, including a series of "Wimsey Papers", the wartime letters of the family, which appeared in the Spectator from November 1939 to January 1940. After that she turned to her translation of Dante and other religious works. Scott-Giles writes that they met often, but he never ventured to bring up the Wimseys.

After her death, he wrote an article on Wimsey heraldry (Coat of Arms, January 1959), and a correspondent discovered a crux. The Wimseys are well-established as being of unbroken succession for sixteen generations (although, as will be seen below, Miss Sayers' genealogy found this too simple) but Gerald Wimsey is described at his trial as "Duke of Denver, in the Peerage of Great Britain and Ireland", which would mean that the title was created after the Union with Ireland, which was passed on 2 July 1800 and came into effect on the following St. Sylvester's Day (New Year's Eve).

Scott-Giles answered this in the manner of a Baker Street Irregular, by assuming that all the data given by Miss Sayers were correct, and coming up with an explanation to save the appearances, and he eventually produced a book on the House of Wimsey. He invented no Wimseys, which explains certain blanks in the list, but he enlarged some from half a sentence.

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