For about 300 years following the Norman Conquest in 1066, the Norman kings and their high nobility spoke only a variety of French called Anglo-Norman. English continued to be the language of the common people. Various contemporary sources suggest that within fifty years of the invasion most of the
While the Anglo-Saxon Chronicle continued until 1154, most other literature from this period was in Old French or Latin. A large number of Norman words were taken into Old English, with many doubling for Old English words (examples include, ox/beef, sheep/mutton and so on). The Norman influence reinforced the continued changes in the language over the following centuries, producing what is now referred to as Middle English. Among the changes was an increase in the use of a unique aspect of English grammar, the "continuous" tenses, with the suffix "-ing". English spelling was also influenced by French in this period, with the /θ/ and /ð/ sounds being spelled th rather than with the Old English letters þ (thorn) and ð (eth), which did not exist in French. The most famous writer from the Middle English period is Geoffrey Chaucer and of his works The Canterbury Tales is the best known.
English literature started to reappear ca 1200, when a changing political climate and the decline in Anglo-Norman made it more respectable. By the end of that century, even the royal court had switched to English. Anglo-Norman remained in use in limited circles somewhat longer, but it had ceased to be a living language.