The Wold Newton Universe is the creation of Science Fiction author Philip Jose Farmer
Farmer postulated that many of the heroic characters of literature are genetically related. According to Farmer the Wold Newton families got their start when a radioactive meteor landed near Wold Newton, in the East Riding of Yorkshire, England on December 13, 1795. You can see a photo of a mounument to the event at http://www.pjfarmer.com/woldnewton/wn_monument1.jpg
The Wold Newton families, traveling in two coaches were exposed to the radiation from the impacting meteorite. According to Farmer the people in the first coach were John Clayton, the third Duke of Greystoke and his wife, the former Alicia Rutherford; Baron George Edward Rutherford, (Alicia’s brother), and his wife Elizabeth Cavendish; Honore Delagardie and his wife, Philippa Drummond; and Fitzwilliam Darcy and his wife, Elizabeth Bennett.
In the second coach were Sir Percy Blakeney, (the Scarlet Pimpernel), and his second wife, Alice Clarke Raffles; Sir Hugh Drummond, (brother of Philippa), and his wife, Georgia Dewhurst; Dr. Siger Holmes and his wife, Violet Clarke Raffles, (the sister of Alice).
Following on horseback was Sebastion Noel, a young medical student and friend of Dr. Holmes. Also present were the coachmen Louis Lupin, Albert Lecoq, Arthur Blake and Simon MacNichols.
The radiation from the meteorite impact caused a number fortuitous mutations in the genetic code of those present. These mutations were reinforced by intermarriage among these families until what Farmer calls a "nova of genetic splendor" was produced. Many of the descendants of the Wold Newton families were endowed with extremely high intelligence, great strength, and an exceptional drive to perform great deeds for good or evil.
The Wold Newton families include:
Tarzan and his son Korak
Doc Savage his cousin Pat Savage, and one of his five aids, Monk Mayfair
Lord Peter Wimsey
Sherlock Holmes and his nemesis Professor Moriarty
The Time Traveler
Fu Manchu and his adversary, Sir Denis Nayland Smith
For further research into Farmers Wold Newton Universe read Tarzan Alive and Doc Savage: His Apocalyptic Life, both by Philip Jose Farmer. Also recommended are W. S. Baring-Gould's Sherlock Holmes of Baker Street and H. W. Starr's articles, "A Case of Identity, or The Adventure of the Seven Claytons," and "A Submersible Subterfuge".
One of the most interesting aspects of the Wold Newton Universe is how it has been taken up and further developed by other writers and fans. The first Wold Newton group that I know of is “The Wold Newton Meteoritics Society,” formed in 1976. The first publication of The Wold Newton Meteoritics Society was The Wold Atlas edited by Timothy J. Rutt. Phillip Jose Farmer was the Honorary Chairman of the society. Five issues of the Wold Atlas were produced, you can view them at http://hometown.aol.com/kickaha23/atlas.html.