'The Comedy of a Duke of Ferrara' in 1598

The 'Comedy of a Duke of Ferrara' is a title of convenience for a lost play associated with the Englische Kömedianten in Germany in 1604. It appears to be linked to an extant German play, Tiberius und Annabella, and therefore to John Marston's The Fawn. This essay discusses a hitherto unnoted reference to the play in English print. The allusion acts as an anchor for all the other records and has implications, not just for the 'Comedy of a Duke of Ferrara', but also for Tiberius und Annabella, The Fawn, and - arguably - Shakespeare's Measure for Measure.