William Shakespeare, the legendary English writer of plays like “Romeo and Juliet,” “Hamlet” and “Macbeth,” may not be their true author, some people believe. One theory, as demonstrated in director Roland Emmerich’s 2011 movie, “Anonymous,” is that Shakespeare did not write any of the plays for which he is credited. On April 23, the same date on which Shakespeare was born and ironically died, let’s look at some of the conspiracy theories swirling about the Bard of Avon’s alleged ghostwriter.

Edward de Vere:

The film “Anonymous” claims it was Edward de Vere, the 17th Earl of Oxford, who was the true author. There is little evidence to support this, but some conspiracy theorists maintain there are codes on some of Shakespeare’s plays that mark de Vere as the real writer, as the Telegraph pointed out. The movie does a good job of constructing a world where Earl of Oxford could feasibly be the “real” Shakespeare.

Sir Francis Bacon:

It was first surmised Sir Francis Bacon, writer of New Atlantis, scientists and essayist, was responsible for Shakespeare’s works in 1856. There is little evidence to support this, other than some of Shakespeare’s plays are similar to Bacon’s.

William Stanley:

Given they have the same initials, William Stanley is a popular possibility. As the Earl of Derby, he had he own theater. He would also sign his name as “Will.” He was also married to Elizabeth de Vere, who was married to William Cecil. This made Cecil a relative of his through marriage. Many believe Polonius from “Hamlet” was based on Cecil.

Christopher Marlowe:

Christopher Marlowe was a playwright and a contemporary of Shakespeare. Marlowe died in a bar fight in 1593, but conspiracy theorists maintain his death was faked so he wouldn’t go to prison for being an atheist.

While there are plenty of theories about the true authorship of Shakespeare's works, Columbia University professor James Shapiro wrote in his 2005 book, "A Year in the Life of William Shakespeare: 1599,” that Shakespeare is the real writer. But it wasn’t enough to convince the doubters.

"I thought I did a damned good job showing that it could only have been Shakespeare who wrote the plays we attributed to him," Shapiro told CNN in 2010. "And I naively thought, that will slow people down who think that Shakespeare didn't write Shakespeare. And they kind of stepped around it.” Shapiro added:  "And I thought, I have to stop and really address this."

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