Near the beginning of Chaucer's General Prologue to The Canterbury Tales, the narrator tells his audience that he will describe the "condicioun" of the pilgrims, their "degree" (social rank), "whiche they were," and also "what array that they were inne"; at the end he says that he has now told their "estaat" and "array" and apologizes if he has not arranged them in the "degree . . . as that they sholde stonde," i.e., their correct social order (NAEL 8, 1.219, lines 38–41; 235, line 718; 236, lines 745–47). This professed concern for putting people in their proper place is obviously of great interest to the poet and his audience. It should also be a matter of interest and amusement to modern readers, especially if they realize that the poet's ostensible concern for propriety is a mask he puts on. What is interesting about Chaucer's Prologue is not that it portrays an archaic and closed social order but that it reveals that order in the process of breaking down. Most of Chaucer's pilgrims are by no means content to stay in their proper places but are engaged in the pursuit of wealth, status, and respectability. The conflict between the old and the new, between tradition and ambition is evident not only in the General Prologue but throughout The Canterbury Tales in the individual pilgrims' prologues and tales.

Every society devises terminology meant to express social stratifications but also often used to disguise them. Class, the principal term in both popular and academic discourse about our society, is not very useful or accurate in analyzing medieval society or the ways in which that society thought about itself. Although there may be some justification in applying notions of class, especially middle-class, to Chaucer's world, that of the late fourteenth century, one needs to keep in mind that the Middle Ages cover the period of a millennium during which social structures and social theory were constantly changing. The main purpose of the following selections is to define more precisely such terms as condition, degree, estate, and order, a word that can signify both the (theoretically) harmonious arrangement of the cosmos and society and individual units of the general order, such as a religious order or an order of chivalry.

One of the main differences between the order of medieval and the order of modern society is the preeminent role played in the former by the Church and its many institutions. One-third of the Canterbury pilgrims either belong to the Church — the Prioress, the Second Nun (her chaplain), the Nun's Priest (one of three priests who are said to accompany her), the Monk, the Friar, the Clerk, and the Parson — or are laymen who make a corrupt living out of it — the Summoner and the Pardoner. >> note 1 The Church was in itself a complex social structure and inevitably constituted one of the divisions made in medieval social theory, which was written in Latin by churchmen. An obvious division is the bipartite one between the clergy and the laity — those belonging to the Church and those outside it. Another — one of several tripartite divisions — which stems from the Roman Church's doctrine of celibacy of the clergy, is based on sexual activity: virgins, widowers and widows, and married people. This is a classification that the Wife of Bath in her Prologue professes to accept while defending her right to remarry as often as she pleases (NAEL 8, 1.256–60).

Religious orders were so called because they were "ordered" or "regulated" by a regula, i.e., a "rule" (the latter noun comes into English from Old French reule via Latin regula), and a division was recognized between regular clergy, those subject to the rule of a monastic order, who lived in a religious community, and secular clergy, those subject to the bishop of a diocese, who lived in the world. Both regulars and seculars were ultimately subject to the pope. The oldest religious rule in this sense is the Rule of Saint Benedict devised in the sixth century by the founder of the Benedictine order, who has been called the "Father of Western Monasticism."

Over the course of the Middle Ages, a schema of three mutually dependent estates developed, one of the earliest articulations of which is that of the English Benedictine monk Aelfric. According to this theory, Christian society was comprised of those who pray (the clergy), those who fight (the nobility), and those who work (the laborers). The clergy see to it that the souls of all may be saved; the laborers see to it that the bodies of all may be fed and clothed; the nobility see to it that the other two estates may carry out their functions in peace and with justice.

In practice, such a schema does not begin to account for the varieties of religious, social, or professional experience during the Middle Ages. The Rule of Saint Benedict sets forth the basic principles and practices of monks and nuns and helps one to grasp the violations of the rule by the likes of Chaucer's fourteenth-century Monk. But the religious and social world kept changing. The Benedictine order itself changed as it grew more powerful and politically influential. In the twelfth century new orders appeared — the Cistercians and the orders of friars founded by St. Dominic and St. Francis. Also, in emulation of the early Christian desert fathers, both men and women often chose to live as hermits or recluses instead of joining religious communities. The Ancrene Riwle (Rule for Anchoresses) (NAEL 8, 1.157–59), written for three English sisters, contains elements of passionate devotional experience absent from the Benedictine rule.

In the twelfth and thirteenth centuries, the nobility developed a taste for romances of chivalry — many of them about King Arthur and the knights of the Round Table. The Round Table itself came to be thought of as an "order," in some respects like a religious order. Ramón Lull's The Book of the Order of Chivalry, one of the most popular works of the Middle Ages, lays out that concept in the form of a book of instruction presented like a rule by an older knight to a young squire who is about to be dubbed into the order of knighthood.

Nuns belonged to religious orders following a rule. But St. Benedict's Rule, Aelfric, Ramón Lull, and most discussions of estates and orders, except those, like Ancrene Riwle, addressed to women, are silent about woman's estate. Women worked beside their husbands in the fields, in the textile industry, and in shops; but there was a body of antifeminist literature that dealt with women as though they belonged to a separate order whose sole enterprise was sex, love, and marriage. In the Romance of the Rose, Jean de Meun, the second of its two authors, created a satiric character named La vieille, the Old Woman, who holds a long discourse on how to take advantage of men and succeed in that enterprise (in which, she confesses, she has failed). Her discourse is an important source for Chaucer's Wife of Bath's Prologue.

Although the three estates were supposed to work together for the common good, their actual history is one of constant friction and conflict. The murder of Thomas á Becket by four of Henry II's knights, for which the king was forced to do penance, is an example of an ongoing dispute between church and state about jurisdiction over the clergy. Mutual hatred of the lower and higher estates is seen in the bloody English Uprising of 1381, which is represented here by a series of rebel manifestos preserved in chronicles and an allegorical diatribe against the rebels in the Vox Clamantis of the poet John Gower. That work, as well as Gower's Mirour de l'Omme, illustrates the late-medieval genre of estates satire to which the General Prologue to the Canterbury Tales is, in some respects, related. In estates satires the idealism projected by St. Benedict, the author of Ancrene Riwle, and Ramón Lull has given way to a profound pessimism and even despair about the social order. The different estates now include — in addition to bishops, monks, barons, knights, and peasants — merchants, doctors, lawyers, and other more specialized professions whose activities provide an unrelieved, if occasionally colorful, catalogue of greed, fraud, and hypocrisy.