The contents of the Shakespeare canon have come into question in recent years as scholars add plays or declare others only partially his work. Now, new literary and historical evidence demonstrates that five heretofore anonymous plays published or performed during his lifetime are actually his first versions of later canonical works.

Three histories, The Famous Victories of Henry the Fifth, The True Tragedy of Richard the Third, and The Troublesome Reign of John; a comedy, The Taming of a Shrew; and a romance, King Leir, are products of Shakespeare's juvenile years. Later in his career, he transformed them into the plays that bear nearly identical titles. Each is strikingly similar to its canonical counterpart in terms of structure, plot and cast, though the texts were entirely rewritten.

Virtually all scholars, critics and editors of Shakespeare have overlooked or disputed the idea that he had anything to do with them. This addition of five plays to the Shakespeare canon introduces a new facet to the authorship debate, and supplies further evidence that the real Shakespeare was Edward de Vere, seventeenth Earl of Oxford.