Chaucer was familiar with many of the framed story-collections circulating in the medieval west and he absorbed and occasionally followed their innovations, but Boccaccio’s Decameron was the only one to exert a decisive influence upon him in the composition of The Canterbury Tales. How thoroughly he knew it, when and where he became acquainted with it, and in what form are still matters of conjecture. Nevertheless, his debt to the Decameron for the overarching structure and plan of the Tales as well as for crucial aspects of narrative technique and content is well established and represents the broad consensus of modern scholarship. The parallels between the General Prologue and Boccaccio’s Introduzione are also striking. Both groups of people meet by chance, agree to go off together the following morning and to divert one another with stories under the direction of a master of ceremonies. Both authors, moreover, defend their literary autonomy by the use of similar authenticating devices (Chaucer in the General Prologue, Boccaccio in his Conclusione Dell’Autore) and see their tales as offering both profit and pleasure.

These similarities, however, are of a general nature. For a precise source of the General Prologue, Helen Cooper proposes the A-text of Piers Plowman as having the “strongest claim to being his direct model”:

Professor Cooper’s argument for the influence of Piers Plowman – and in particular the A-text of the poem – is strong and persuasive.