Middle English is the name given by historical linguists to the diverse forms of the English language in use between the late 11th century and about 1470, when the Chancery Standard, a form of London-based English, began to become widespread, a process aided by the introduction of the printing press to England by William Caxton in the late 1470s. written Middle English displays a wide variety of scribal (and presumably dialectal) forms.
The Middle English dialects can be divided into five major groups:
South-Western --West Saxon;
South-Eastern-- a continuation of OE Kentish;
East Midland -- in the eastern part of the OE Mercian area;
West Midland--- the western part of the OE Mercian area;
Northern (N), north of the Humber.
In general, southern Middle English dialects tend to be more conservative and northern dialects more progressive. This is particularly noticeable in the case of the West Midland dialect, which is primarily preserved in two major text groups. One of these is early and from the southern part of the West Midland area; the other one is later and from the northern part of the West Midland area. The language variants of the two text groups differ in many respects, the early group having much in common with the South-Western dialect, the later group having more in common with the Northern dialect. Features representing the two forms of the West Midland dialect are separated by a semicolon in the presentation of forms and dialect features below.
Geoffrey Chaucer was an English author, poet, philosopher, bureaucrat, courtier and diplomat. Although he wrote many works, he is best remembered for his unfinished frame narrative The Canterbury Tales. Sometimes called the father of English literature, Chaucer is credited by some scholars as the first author to demonstrate the artistic legitimacy of the vernacular English language, rather than French or Latin.