PaneSlide's chapters each restore a stained-glass window in the House. The real art form behind that idea is well over a thousand years old. This guide is a short, careful history: the key steps, a few famous places, and how a traditional window is put together.
Coloured glass before windows
People were making coloured glass long before anyone built a stained-glass window. Glass beads and small vessels were made in Mesopotamia and Egypt thousands of years ago, and Roman glassmakers were highly skilled.
One Roman object shows how sophisticated they were: the Lycurgus Cup, made in the 4th century and now in the British Museum. Its glass looks green with light on the front and red with light shining through it. Modern analysis found tiny particles of gold and silver spread through the glass. It is not a window, but it shows that colour in glass was already being controlled with great skill.
The oldest surviving windows
Coloured glass was used in church windows from early Christian times, but very little early glass survives. Among the oldest windows still in place are five figures of prophets in Augsburg Cathedral in Germany, usually dated to the late 11th or early 12th century. They show David, Jonah, Daniel, Moses and Hosea as tall, calm standing figures.
At about the same time, a monk writing under the name Theophilus produced On Various Arts, probably between 1100 and 1120. Its second book explains how to make glass, cut it, paint it and set it in lead. It is one of the most important early descriptions of how stained glass was made, and many of its steps are still recognisable today.
The great Gothic windows
The Gothic style of architecture, from the 12th century onwards, made walls thinner and windows much larger. Builders could now fill whole walls with glass.
- Chartres Cathedral in France keeps one of the largest collections of medieval stained glass, much of it from the early 13th century. Its deep blues are famous.
- The Sainte-Chapelle in Paris was built for King Louis IX and consecrated in 1248. Its upper chapel has fifteen huge windows from the mid-13th century, so tall and close together that the walls seem to be made of coloured light.
Windows like these told stories from the Bible and the lives of saints in many small scenes, read from bottom to top. For people who could not read, they were picture books as well as decoration.
New techniques
Stained glass kept changing.
- Silver stain, introduced in the early 14th century, let artists paint a compound of silver on clear glass and fire it to get shades of yellow and gold. For the first time, yellow and clear could appear on the same piece without a lead line between them.
- Painted enamels later allowed several colours to be painted onto one piece of glass, making windows more like paintings.
- In the 19th century, a revival of medieval styles brought a huge wave of new church windows across Europe and North America.
Opalescent glass and Tiffany
In the United States, artists experimented with opalescent glass, which is milky and streaked rather than clear. John La Farge patented a type of opalescent window glass in 1880. Louis Comfort Tiffany (1848 to 1933) and his studios became famous for windows and lamps that used this glass to create shading and texture with very little painting.
Tiffany's studios are also strongly associated with the copper foil method. Instead of setting each piece of glass in lead, its edges are wrapped in thin copper tape and soldered together. This allows much smaller, more detailed pieces, which suits lampshades and curved shapes.
How a traditional window is made
The steps have changed surprisingly little since Theophilus:
- Design. The artist draws a small design, then a full-size drawing called a cartoon, showing every piece and every lead line.
- Cut. Each piece is cut from sheets of coloured glass to match the cartoon.
- Paint and fire. Details such as faces and folds are painted on with dark glass paint and fired in a kiln so the paint fuses to the glass.
- Lead. The pieces are fitted into strips of lead called cames, which have an H-shaped cross-section that holds glass on both sides. The joints are soldered.
- Cement and fix. The panel is waterproofed with a putty-like cement, then fixed into the window opening with metal bars for support.
The dark lead lines are part of the design, not just structure. They outline shapes and make the colours glow brighter by contrast.
The link with PaneSlide
PaneSlide borrows the feel of stained glass rather than its methods. Each chapter's window in the House is made of 20 pieces, and each level you clear lights one, with the boss completing it. On the board, the dark frames between cells play the part of lead lines, and overlapping panes mix colour the way layered glass really does.
If you are curious about the chemistry behind the colours, read why glass is coloured.
Sources
- Wikipedia, "Lycurgus Cup", checked 29 October 2026.
- Wikipedia, "Augsburg Cathedral" (prophet windows, late 11th to early 12th century), checked 29 October 2026.
- Wikipedia, "Theophilus Presbyter" (De diversis artibus, probably 1100 to 1120), checked 29 October 2026.
- Wikipedia, "Sainte-Chapelle" (consecrated 26 April 1248; fifteen windows), checked 29 October 2026.
- Wikipedia, "Came glasswork" (lead and copper foil methods), checked 29 October 2026.