Medieval stained glass

The tradition & historical record

Medieval stained glass is the colored and painted glass of medieval Europe from the 10th century to the 16th century. For much of this period stained glass windows were the major pictorial art form, particularly in northern France, Germany and England, where windows tended to be larger than in southern Europe (in Italy, for example, frescos were more common). In some countries, such as Sweden and England, only a small number of original stained windows have survived to this day. Stained glass windows were used predominantly in churches, but were also found in wealthy domestic settings and public buildings such as town halls, though surviving examples of secular glass are rather rare in comparison. Stained glass windows were used in churches to enhance their beauty and to inform the viewer through narrative or symbolism. The subject matter was generally religious in churches, though "portraits" and heraldry were often included. ¹

Window glass was recorded as being in use as early as the 8th century CE with colored window glass displayed in religious buildings. One of the earliest known examples of stained glass is from the Baume-Les-Messieurs abbey in Jura, France, which showcases large stained glass windows surrounding an altar. The Baume-Les-Messieurs Monastery provided the framework for the stained glass of the early medieval period. The glass in early middle ages was simple and mostly used in small amounts, often alongside other materials like mosaics. The thick opaque glass consisted of basic colors such as red, blue, and green, creating geometric designs instead of detailed pictures. The glass was made from heating sand, lime, and soda ash in a furnace which created a murky color that limited light exposure. Early stained glass windows were not only decorative but also educational. They conveyed biblical stories and moral lessons to largely illiterate people. This made the church more inclusive and able to reach a broader range of people. ¹

The Romanesque period began in the 11th and 12th century with the revival of Roman architecture. The revival combined traditions of Roman architecture with stained glass. Eventually, Romanesque stained glass became its own entity, developing into a new style. This new style was used in Romanesque style churches throughout Europe. Romanesque stained glass windows were often smaller and made from thick, colorful glass, with bold lines that formed simple, clear images. The glass pieces were held together by thick lead strips, creating a graphic and sometimes blocky appearance compared to later styles. The windows often showed scenes from the Bible and the lives of saints. While there are not many surviving examples of Romanesque stained glass, some can still be found in churches like Saint-Denis in Normandy and Saint-Sernin in Toulouse. This style of stained glass influenced the later Gothic style, which had larger windows and thinner glass. Although Gothic stained glass became more famous for its detailed and intricate designs, Romanesque stained glass played a key role in shaping stained glass art and spreading religious messages. ¹

The late medieval period, often referred to as the Gothic Era, ranged from the 14th to the 16th century and marked a significant evolution in stained glass artistry. This era saw advancements in both the technical aspects of glassmaking and the complexity of window designs. The most significant change in stained glass from the Romanesque to the Gothic Era was the increased use of glass painting techniques, which allowed for greater detail and narrative depth in the imagery. Artists began to employ more refined methods of shading and highlighting, enhancing the three-dimensionality of figures depicted in the glass. Glassmakers experimented with different additives and firing techniques to create a wider range of colors. These colors included rich purples, deep blues, and vibrant greens. These new colors added depth and richness to the stained glass windows, further enhancing their visual impact. This new technique is seen in the Evreux Cathedral in France. The Cathedral began development in the 13th century and was not finished until the 17th century. The glass making took place in the 14th and 15th centuries and exemplified the stained glass of the late middle ages. The stained glass portrayed Christ and the Virgin Mary in a more three dimensional form than earlier stained glass designs. Each panel of glass depicts Jesus and Mary in the bible that had not previously been seen in three dimensional form on glass windows. ¹

Prior to c. 1000, most coloured glass was of a soda-lime-silica composition. In Northern Europe soda glass was eventually almost totally superseded by potash-lime-silica glass (Forest glass). Forest glass continued to be used in stained glass for the duration of the medieval period until soda glass again began to be used in the 16th century. The potash (K2O) found in Forest Glass was derived from wood ash. In De diversis artibus, Theophilusdescribes the use of beech wood as the preferred source of ash. Other plant matter, such as bracken, was also used. As well as containing potash, beech ash comprises an assortment of compounds including iron and manganese oxides, which are particularly important for generating colour in glass. Medieval stained glass panels could be created either by the cylinder blown sheet or crown glass (window) method. Forest glass was manufactured in Burgundy and Lorraine near the Rhein; in Flanders; and in Normandy, in the Seine and Loire Valleys. It was distributed throughout mainland north-west Europe and Britain in the form of ready-made sheets. The application of painted decoration to and final shaping of the sheets was carried out at glass working centres close by the final destination of the glass. ¹

The color of glass could be affected by many factors. Sources of silica were often impure, with iron oxide being one of the most common impurities. The greenish hue of uncolored glass is usually owing to the presence of a mixture of ferrous (Fe2+) and ferric (Fe3+) ions in the glass matrix. It is also possible that 'impurities' could be introduced at the fritting stage within the glass furnace, leading to the addition of further alumina, silica and iron oxides. ¹

The text above is adapted from the Wikipedia article “Medieval stained glass”, available under the Creative Commons Attribution-ShareAlike 4.0 licence. ¹

Medieval stained glass is coloured and painted glass of medieval Europe, according to the structured record cited below. This entry was generated automatically from that record and has not yet been reviewed by a person familiar with the tradition. ²

The source record links this tradition to 1 external register, which can be verified through the citation. ²