Romeo and Juliet Prologue

Romeo and Juliet is already written in some metaphysical sense because that's the genre of tragedy. In a more local sense it's already written because as these lectures always end up saying the story pre-exists Shakespeare. The direct source Shakespeare is using is the long poem by Arthur Brooke, translated from the Italian under the title The Tragical History of Romeo and Juliet, published in 1562. That's quite a useful poem to put alongside Shakespeare's chorus.