SHE is the Hampshire woman who was involved in one of the greatest hidden scandals of the 16th century.

Elizabeth Wriothesley, the third countess of Southampton, had a passionate affair with William Shakespeare.

And 400 years later amazing new research has revealed that the resulting love child could be an ancestor of our future king.

A leading German academic says the link was made when their illegitimate daughter Penelope married an ancestor of Princess Diana.

The claims, by Hildegard Hammer-schmidt-Hummel, are set to throw literary scholars into a renewed frenzy of debate on Shakespeare in love.

She believes there is strong pictorial evidence showing the world's most famous playwright is indeed an ancestor of Prince William.

Her argument hinges on a painting of a previously unidentified woman who she claims is the so-called Dark Lady, Shakespeare's lover.

In a forthcoming book, she says the likeness is identical to Elizabeth Wriothesley.

Hammerschmidt-Hummel says Penelope was born in 1598 and went on to marry the second Baron Spencer, of whom Princess Diana was a descendant.

Ten weeks before Penelope's birth, Elizabeth married Shakespeare's patron, Henry Wriothesley, third earl of Southampton.

He became friendly with Shakespeare in the 1590s when a plague outbreak caused theatres in London to close, prompting the Bard to head out of the capital.

It is probable that he stayed with the Earl at the nobleman's seat on the site of the old Titchfield Abbey, where he could have met Elizabeth.

To thank the Earl for becoming his patron, Shakespeare dedicated two poems to him - Venus and Adonis and the Rape of Lucrece.

Hammerschmidt-Hummel, a lecturer in English literature at Mainz University, has already stirred controversy by producing a detailed likeness of Shakespeare from a death mask.

Her work is known to be thorough, but rival experts have said only DNA testing will prove her claim that he died from eye cancer.

The royal link, to be detailed next month in her book The Secrets of Shakespeare's Dark Lady, has immediately ignited debate.

Dr Jonathan Sawday, of the English department at Southampton University, said he would remain sceptical until the claims could be further analysed.

Professor Richard Wilson of Lancaster University was more scathing, saying German academics were simply desperate for a share of "the Shakespeare industry".

He said: "There are as many theories about the Dark Lady as there are Shakespeare scholars. The Dark Lady could be a complete red herring."

Russell Jackson, deputy director of the Shakespeare Institute in Stratford-upon-Avon, said: "This is an extraordinary story but the facts are difficult to prove. There will be a lot of debate about this."

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