The 15th century saw a great growth and intensification of the individualism we have already noted as arising in the 14th cen tury. Such a development naturally gave rise to the dominance of artists of unusual talent, and to the formation of schools dependent on such artists. A distinct style became established as a local tradition and sometimes persisted over two or three generations. Such schools were formed all over Europe, and particularly in the great ecclesiastical cities. In England, for example, definite schools can be associated with York, Coventry, Canterbury, Winchester, Oxford, Gloucester, Wells, Lincoln, Nor wich and Westminster.
The different styles are not always easy to distinguish, and the "schools" are rather in the nature of empirical groupings based on the density of distribution.
Towards the end of the i 5th century England suffered a general invasion' of foreign artists and craftsmen, a growing in flux that reached its culmination early in the next century with the arrival of Torrigiano and Holbein. At this time, in the Netherlands, the art of stained glass had reached a development which, in accomplishment and modernity, was far ahead of the insular style in vogue among English glass-painters. The wool and cloth trades flourished in spite of the wars. The new merchants, earnest Lollards as they were, were eager to turn their wealth to some good purpose, and thus they made the 15th century an age of church building and charitable foundations. And these merchants, moreover, were men of some culture, whose business had brought them into contact with foreign luxuries— particularly those of the Netherlands. When, therefore, they re quired glass for the beautifully furnished churches which they began to construct in various parts of the country, they demanded glass in keeping with their luxurious tastes, and for this they turned to the men from the Netherlands. In answer to the de mand these men came across and, in accordance with the regulations, established themselves within a recognized sanctuary such as the liberty of St. Thomas in Southwark, and assumed English names. As time went on, they became a menace to the existence of the London Company or Gild of Glaziers, and a continual series of disputes between the Gild and the foreigners marks the beginning of the i6th century. But the proper tra dition of glass-painting was entirely lost. In the middle ages stained glass thrived as an art subordinate to, or in community with, architecture. With the Renaissance, and the shifting of the dominant emphasis of artistic effort from architecture to painting, the glass-painter found himself in a dilemma. He had to adapt his art to the new conditions, or suffer from the general neglect of arts subordinate to architecture. He attempted to save him self by adopting the aesthetics of painting, and the history of stained glass henceforth is the history of this false step and of all the disastrous consequences.
treatment of the windows on the largest possible scale ; the win dow is regarded as one large canvas; the intersecting mullions are ignored. On this canvas the coloured glass is spread in generous masses and heightened by all the resources of line and shade. The windows gleam with everything that is rich and ornate in colour, design and subject. The glass is thin, but this fault is counteracted by the breadth of the treatment. The Nether landish type is well represented in England by the work of im ported artists, of whom Barnard Flower is the most important. This artist came from the Netherlands, probably encouraged by Henry VII., who made him king's glazier in 1505. Flower executed the whole of the windows for Henry VII.'s chapel at Westminster, and was entrusted with the contract for King's College chapel, Cambridge, but died before he had completed more than four of the windows. It is probable that among the work which may be attributed to Flower are the windows of Fairford church in Gloucestershire, perhaps the most complete unit of stained glass remaining intact in England. King's College chapel, begun by Flower after designs probably by the Flemish artist, Dirick Vellert, was completed by a mixed company of English and Flemish glaziers.
In France, Rouen was the great centre of glass-painting, and that city still offers an incomparable display of the glass of this period, though many other towns, such as Evreux, Chalons-sur Marne, Dreux, Beauvais, Auch, Troyes and Montmorency, are famous for their windows. In the Netherlands, the most important windows of this period are found in Antwerp, Hoogstraten, Brus sels, Liege and Amsterdam, whilst the windows at Gouda, painted by the brothers Dirk and Waiter Crabeth and their pupils, towards the end of the i6th century, are of extraordinary range and completeness. In Germany important schools existed at Strasbourg, Augsburg, Munich, Freiburg-im-Breisgau, Nurem berg, and above all at Cologne, the general character of all of which was not essentially different from that of the dominant Flemish or French type. In Italy the period is mainly associated with the name of Guglielmo de Marcillat (1467-1529, sometimes erroneously called William of Marseilles). Windows known to have been made by him exist at Arezzo and Rome, and a very typical example from the cathedral of Cortona, dated 1516, is in the Victoria and Albert Museum. At Florence, where there are also important earlier windows in the cathedral which are said to have been designed by Ghiberti and Donatello, other windows in the style of Marcillat may be seen in the church of Santa Croce. The building of the cathedral at Milan caused an important school of glass-painting to develop there, and the work of Cristoforo de Mottios and Nicolo da Varallo carried out during the second half of the 15th century is of great beauty. The Milan school continued in full activity during the i6th and 57th centuries. In Spain, especially at Seville, Leon and Avila, magnificent windows of this period exist, but they are in all cases the work of Flemish glass-painters.