The main difference between Chaucer's language and our own is in the pronunciation of the "long" vowels. The consonants remain generally the same, though Chaucer rolled his r's, sometimes dropped his aitches, and pronounced both elements of consonant combinations, such as "kn," that were later simplified. And the short vowels are very similar in Middle and Modern English. But the "long" vowels are regularly and strikingly different. This is due to what is called The Great Vowel Shift.

Beginning in the twelfth century and continuing until the eighteenth century (but with its main effects in the fifteenth and early sixteenth centuries) the sounds of the long stressed vowels in English changed their places of articulation (i.e., how the sounds are made).

Old and Middle English were written in the Latin alphabet and the vowels were represented by the letters assigned to the sounds in Latin. For example, Middle English "long e" in Chaucer's "sheep" had the value of Latin "e" (and sounded like Modern English "shape" [/e/] in the International Phonetic Alphabet [IPA]). It had much the same value as written long e has in most modern European languages. Consequently, one can read Chaucer's long vowels with the same values as in Latin or any continental European language and come pretty close to the Middle English values.

The Great Vowels Shift changed all that; by the end of the sixteenth century the "e" in "sheep" sounded like that in Modern English "sheep" or "meet" [IPA /i/]. To many it seemed that the pronunciation of English had moved so far from its visual representation that a new alphabet was needed, and in the sixteenth century we have the first attempts to "reform" English spellings, a movement still active today. In 1569 John Hart (in his Orthographie) went so far as to devise a new phonetic alphabet to remedy what he considered a fatal flaw in our system of language. (His alphabet and the work of other language reformers provides us with our best evidence for the pronunciation of English in his time).

To understand how English changed (not why; no one knows) one must first note that vowels are articulated in particular parts of the mouth; we make the sound in Modern English "deep" [/dip/] with our tongue forward and high in the mouthr, and the sound in Modern English "boat" [/bot/] with our tongue lowered and drawn toward the back of the mouth and the jaw relatively low (open). Say "ee" (or "beet") and "o" (or "boat") in succession and you may be able to feel the movement of your tongue from front to back.

This chart roughly represents the places where the "long vowels" are articulated:

[The "au" representing the low back vowel above is there because I cannot find a way to print a backward c, the usual means of representing this sound.]

The Great Vowel shift invloved a regular movement of the places of articulation: The front vowels each moved up a notch, except for /i:/, which formed a dipthong. Likewise the back vowels moved up, except for /u:/, which formed another dipthong:

To hear the sounds Click Here. Then Click Here.

Note that the change affects only long, stressed vowels. The "y" in Middle Enghlish "my" was affected because it has primary stress, and we say /mai/; the "y" in a word like "only" was not affected (the primary stress is on the first syllable and -ly lacks stress, so we say /li:/, making the -ly of "only" rime with "see."

The change is not as neat as is shown; /æ:/ ("open e," as it is called in most discussions) did not complete the movement from /æ:/ to /e:/ to /i:/ (contrast Mod. Eng. "break" and "beak"). Moreover, when Middle English "e" represents /æ:/ and when the spelling "o" or "oo" represents the open vowel often can be determined only by the etymology of the words. Modern spellings offer a clue: as a general rule, where modern English uses "ea" (as in "read") or "oa" (as in loaf), the Middle English equivalent was the open vowel sound. ("Open" and "close" or "closed" refer to the jaw -- lowered for "open" and raised for "close" vowels.)

There are other, more exact but more complex, ways of representing the change. (There is also an excellent presentation -- See and Hear the Great Vowel Shift on The Great Vowel Shift site maintained by Melinda Menzer at Furman University.) Moreover, our best attempts at recovering Chaucer's pronunciation can be only approximations. Nevertheless the following chart will provide a guide to the pronunciation of Chaucer's "long vowels":

 To hear the sounds, Click Here.

See any history of the English Language (e.g., A.C. Baugh, rev. Thomas Cable, A History of the English Language [PE 1075 .B3]) for further details. A full account of Chaucer's pronunciation is in the section on language, by Norman Davis, in The Riverside Chaucer