The identity of the man Shakespeare's book of sonnets was dedicated to - an enigma that has puzzled scholars for centuries - may now finally have been established.

The first edition of Shakespeare's sonnets, published in 1609, were dedicated to a 'Mr WH', whose identity has never been proven - leading to claims it could have been a male lover.

But an American researcher has now uncovered evidence to suggest he was not, in fact, a male lover or nobleman, but a recently deceased friend of the sonnets' publisher.

Inscribed in the first published edition of the sonnets is a dedication to the man, whose identity has been subjected to fierce debate for centuries.

The message reads: 'To the only begetter of these ensuing sonnets Mr WH. All happiness and that eternity promised by our ever-living poet wisheth the well-wishing adventurer in setting forth.'

It ends with the letters 'IT' -believed to be the mark of the sonnets' publisher, Thomas Thorpe.

The Guardian reported researcher Geoffrey Caveney has now found evidence linking the initials to William Holme, who was an associate ofThorpe's.

The two were both publishing apprentices in London, had theatre connections and came from prominent families in Chester.

Caveney said evidence for his conclusions included that Holme died two years before the sonnets were published and it would have been an insult to refer to an aristocrat as 'Mr' - ruling out Mr WH's identity as a nobleman.

His theory, that it was a tribute to someone deceased, would also explain the spiritual theme of the message.

"Nobody was aware that there was [also] a publisher of that name who had died in 1607. Seeing the dedication as a memorial makes a lot of sense," said Caveney according to the Guardian.

Throughout the centuries since the sonnets were published, speculation about Mr WH's identity has varied wildly.

The most likely candidates were often thought to have been his friends Henry Wriothesley, Earl of Southampton, or William Herbert, Earl of Pembroke.

Oscar Wilde explored a different theory, writing a fictional 1889 story about whether it could be a cross-dressing boy actor called Willie Hughes - and the same person as the 'fair youth' of the sonnets.

That could also help explain punning references to the name 'Will', it was claimed.