This remarkable rapid shift in ideas is bound up with social and economic developments of Christendom in the twelfth and thirteenth centuries. They include the well-known growth of towns.  There is also the steady enrichment of the countryside. The water mill became a supplement to animal power, introduced to several countries of northwest Christendom by the Cistercians and was followed shortly by the windmill. The techniques of metallurgy and mining advanced. In many regions, feudal control of the peasantry began to losing its force. The steady development of trade, both south and north, in Italy and Flanders and on the Baltic coast, distributed textiles, rare commodities, resources that enriched and knitted together the lands touched by it. A growing money economy in the towns is one condition of that progress. Almost the only lands that are in decay are southern Italy and southern France, both ruined by endless violence.

Elsewhere, enough new wealth was created to provide for all manner of crusades and wars, with enough over to allow of the extraordinary episode of cathedral building.  A slowly growing population supported banditry and wars and provided recruits to the towns and to the new mendicant orders. Secular powers found it convenient to turn to bankers and money-changers to mobilize wealth for some extravagant enterprise or other. Last but not least, these secular powers, whether king or baron or municipality, were in fact becoming stronger, and larger.

The great increase in wealth of thirteenth-century towns and their guilds allowed a spill-over of resources into municipal building, often on a grand scale, decorated with Gothic styles and motifs. The textile centres of north-west Europe offer many examples, such as the palatial Cloth Hall at Ypres, of these kinds of civic project.  Such buildings provided models for the Gothic Revival public works of a heritage- minded nineteenth century.  This fact alone illustrates the principle of how the great visual characterising features of European culture have persisted so as to have a place in our heritage.

The first images of nature as most people would recognise it emerged in European sculpture within the space of a few decades around 1200.

Up to then, the conventions of church sculpture have a general family likeness to which we give the name of Romanesque. This style has its origins in Constantinople.  It spread into the West via sixth-century Ravenna and the changing cultural norms of the ninth-century Carolingian kingdom.

Romanesque sculpture is heavily stylised.  This is evident in the gesture of a figure, the rendering of facial expression, the stiff posture of a divine judge, the patterning of drapery, the near- abstraction of elaborate foliage or of mystic creatures adorning a pillar.  It also has a heavily loaded language, which is hieratic, symbolic, and not quite of this world.  It tells us about supernatural things, and the terms it uses are formalized to deliver sacred import. Nature, particular the human form, is in fact transformed into mystic symbols, and representation is subordinated to moral significance.

The new sculpture that emerges in the figures that decorate the cathedral of Chartres bears movingly human expressions.  Gestures lose their stiffness; the folds of a robe flow not only beautifully but in obedience to the laws of Nature. A leaf is recognizably a leaf of a known species of tree and not an elaborate part of mystic ornamentation. These poses, faces, draperies, leaves, are evidence that a craftsman is capturing the forms around him in a new way, and there are more and more craftsmen following the fashion and developing it.  The craftsmen gradually turn their backs on an age-old tradition, adventuring into new language and presenting the viewers with a new kind of everyday experience.  For example, there is a contemporary Parisian story, written for the urban man in the street, about two countryfolk who have come to see the statuary at Notre- Dame.  One says to the other in his patois, 'Look! That's King Pepin! There's Charlemagne!' and as they stand absorbed, gazing upwards, a cutpurse relieves them of their savings. Such a glimpse of a scene, which looks trivial, is in fact quite revealing. To begin with, the 'sightseers' in Paris are carrying coins in a purse: a hundred years earlier the money economy is so little developed as to make that detail unlikely. More to the point, before the thirteenth century no one, clerk or rustic, would have been expecting to look up at a church and see on it a row of historical figures representing, and looking like heroes of the age and not merely symbolic figures.

The first piece of profane literature which presents naturalism in a striking way is Jean de Meung's famous continuation (1275) of the Roman de la Rose—a poem written by Guillaume de Lorris in Paris in 1235.  In its original form it is an allegory of love. Jean de Meung transforms the original intention of the poem when he adds his fourteen thousand extra lines. Instead of an allegory of refined courtesy, he gives us a philosophy in which 'Nature' is personified as really the creator and mover of all things. The potency of Nature is closely woven in with the theme of generation— sexuality. The modern expression is of this medieval justaposition is Carl Orf's musical extravaganza, Carmina Burana.

At a slightly earlier date, probably around 1220, St. Francis of Assisi, far away from Paris, composes his unforgettable rhapsodies to 'Brother Sun' and to the birds and beasts and beauties of God's creation. We must suppose that an echo of this joy is carried across Christendom by some at least of Francis's wandering band of followers, the Fraticelli. 

A little earlier than Francis's hymn, a quite different kind of person, Geoffroy de Villehardouin, writes his eyewitness chronicle of the Conquest of Constantinople (between 1205 and 1213). His book is the first great work of historical prose to be written in French instead of Latin.  Is this narrative there is evidence that public affairs are beginning to be seen in a more 'naturalist' way than formerly. In common with many others of his day, he is prepared to stand his ground and offer his own reading of the will of God. By the mid-thirteenth century, the Dominicans made it respectable to take a curious interest in Nature.