Written sometime in the 1380s, The Canterbury Tales -- the first selection of short stories in English -- is about a group of pilgrims who agree to tell stories while they travel together to Canterbury, the seat of the English Church (still Catholic) and the site of the shrine dedicated to Thomas a Beckett, who was martyred for his faith. This telling of tales by the pilgrims is the frame story.
The idea of a frame story (story within a story) comes from a long tradition: The Arabian Nights and The Decameron. Chaucer read The Decameron when he visited Italy. Chaucer borrows some of his stories from The Decameron but he improves on it by describing the story tellers in fascinating detail and matching the stories to the story teller's personality. For instance, the chivalrous and courtly knight tells a story of courtly love while the Nun's Priest tells a gentle story of farm animals. All of Chaucer's stories have a moral: in keeping with Augustine's admonition that literature should not be entertaining, but should instruct the souls of humankind. In reading Chaucer, we must strip the chaff from the grain, as Augustine instructed, to find the real meaning of the story; for example, the "Nun's Priest's Tale" is not really about a rooster and a fox but about something very human we can all learn from.
On one hand, Augustine who shaped the early Church and whose opinions became virtual laws for the Middle Ages (medieval age) would have approved of Chaucer, writing almost 1000 years later, if he were convinced that the tales were not just entertainment but had serious moral value. But would he be convinced? Many readers have found the tales more entertaining than moral. Chaucer, himself, was conflicted, and on his deathbed retracted the tales, presumably because he was afraid to face judgment before God with such bawdy stories as part of his life's work.
The language of Chaucer -- Middle English -- is closer to Old English (the language of the Anglo-Saxons) and Norman French (the language of William the Conqueror -- invasion, 1066).
Originally, he proposed 124 stories; he actually wrote 24.
Subject matter: sex, lust, greed, jealousy, native cunning (tricksters), the credulousness of the stupid, marital problems, infidelity, corruption of the church.
The Canterbury Tales is a cross section of medieval society: feudal (the knight), ecclesiastical (pardoner, priest, nun), urban (lawyer, doctor, merchant). And Chaucer's interest in middle class characters, such as a cook, carpenter, miller, lawyer, merchant, clerk, physician reflects the rise of the middle class in the fourteenth century.
Literature is moving away from the questions of the genre, romance (King Arthur tales), to a more personal vision, a domestic vision. Chaucer is interested in individuals, their foibles and individual differences; he is interested in realism. This interest in realism is new in the medieval age and signals the rise of new age, the Renaissance.
Chaucer is one of the most interesting writers in English literature because he straddles two worlds: the Middle Ages and the Renaissance. In many ways he is very much a medieval figure: his stories can all be read as allegory which was the only acceptable form of literature in the church-dominated middle ages. (See information on Augustine's influence on literature.) But he also takes an interest in the individuality of his characters that is more in keeping with the artists of the Renaissance. (Compare Medieval painting and Renaissance painting on the CD to get a sense of what I'm talking about.)
Chaucer was lucky enough to be a diplomat for England and traveled to Italy in the early fourteenth century when and where the Renaissance began. The rest of Europe in the fourteenth century was firmly rooted in the traditions of the Middle Ages. Perhaps his contact with the Italians gave him this unique quality.