Plagiarism software more commonly used to check student essays for overly assiduous borrowings has uncovered a long-forgotten, handwritten document from 1576 as the possible source for more than 20 monologues and passages from Shakespeare’s plays.

Independent scholar Dennis McCarthy and LaFayette College professor June Schlueter used WCopyfind software to compare passages from Shakespeare’s plays with George North’s 1576 unpublished manuscript, A Brief Discourse of Rebellion, about the dangers of rebelling against a king. They were able to trace more than 20 passages back to the essay, including Gloucester’s opening soliloquy in Richard III, Macbeth’s comparison of dog breeds to different classes of men, the Fool’s Merlin prophecy in King Lear, and the events surrounding Jack Cade’s fatal fight with Alexander Iden in Henry VI.
“Until now, no Shakespeare scholar has studied the manuscript, and it has probably remained little read. Yet, as our analysis has revealed, Discourse is not merely the only uniquely existent, evidently uncopied document to have had a substantial impact on the canon; it is one of the most influential Shakespearean source texts in any form,” they write in a new book, A Brief Discourse of Rebellion and Rebels by George North, which is published on 16 February by Boydell & Brewer, in collaboration with the British Library. “In terms of the number of plays, scenes and passages affected, the scope of the manuscript’s influence likely exceeds all other known Shakespearean sources, excepting only the Chronicles of Hall and Holinshed and Thomas North’s Plutarch’s Lives.”

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