Chaucer’s London, with a population of around 50,000, had experienced considerable immigration from the Home Counties, Midlands and elsewhere in England in the fourteenth century. In addition to accommodating such incomers, Londoners would also regularly come across Scots, Welsh, Irish, Flemings, Florentines, and Hanseatics. This was, then, a city of multiple identities and shifting linguistic variety. Variation and change therefore characterised London texts and the development of London English during the late medieval period. Chaucer was particularly sensitive to such variation – to geographical distinctions and to emerging social differences articulated linguistically: this shows in his appreciation of the position of French in England as well as of the various ‘Englishes’ that he would have encountered. Chaucer’s verse reveals a writer exceptionally aware of the languages around him, whether he is contrasting the Knight with the Miller, or re-performing Northern speech in his Reeve’s Tale. All in all, the rich range of socio-linguistic usages available in the language of London gave Chaucer numerous opportunities for the literary invention that typifies his achievement.

Thomas Hoccleve referred to Chaucer as the ‘firste fyndere of our faire langage’. The word fyndere is carefully chosen, as a modified translation of the first ‘canon’ of classical and medieval rhetoric, the ancestor of present-day English invention. Any assessment of Chaucer’s ‘poetic art’ requires us not just to identify the linguistic choices available to him, it also requires us to ask how those choices relate to his broader poetics. Chaucer’s use of ‘pronouns of power’, for example, do not only characterise particular choices from the linguistic resources of London Middle English, they are also a matter of style, a notion for which classical and medieval literary theoreticians had their own terminology, distinguishing high, middle and low styles, widely recognised as having distinct functions relating to social status and roles. It is conceivably as a metrist, however, that Chaucer’s skill as a ‘finder’ is perhaps most subtly demonstrated, as examples from his works show.