The Prince Tudor theory (also known as Tudor Rose theory) is a variant of the Oxfordian theory of Shakespeare authorship, which asserts that Edward de Vere, 17th Earl of Oxford was the true author of the works published under the name of William Shakespeare. The Prince Tudor variant holds that Oxford and Queen Elizabeth I were lovers and had a child who was raised as Henry Wriothesley, 3rd Earl of Southampton. The theory followed earlier arguments that Francis Bacon was a son of the queen. A later version of the theory, known as "Prince Tudor II" states that Oxford was himself a son of the queen, and thus the father of his own half-brother.
This hidden history is supposed to explain why Oxford dedicated the narrative poems Venus and Adonis (1593) and The Rape of Lucrece (1594) to Southampton and to explain aspects of the poems' contents. The content of Shakespeare's sonnets has also been used to support the theory, as, to a lesser extent, have episodes in the plays.
The Prince Tudor theory has created a division among Oxfordians. Many orthodox Oxfordians regard the theory as an impediment to Oxford's recognition as Shakespeare, whereas the Prince Tudor theorists maintain that their theory better explains Oxford's life and the reasons for his writing under a pen name
There are variants on this theory.
More information on the Wikipedia page .