Credited to Morocco. Zellij developed across the western Islamic world, not in Morocco alone. Early glazed tile decoration is recorded at Hammadid palaces in present-day Algeria and in early Islamic sites in Tunisia, and the mature technique is shared with al-Andalus. Morocco's claim rests on early dated examples such as the Kutubiyya minaret and on being the only country where the craft never stopped.
How it began
The technique of mosaic tilework was probably inspired by Byzantine mosaics and adapted by Muslim craftsmen to glazed ceramic. Its origins are placed between the 10th and 13th centuries. One history of the craft says it was born in Morocco in the 10th century in white and brown tones, in imitation of Roman mosaics. The glazed tiles on the minaret of the Kutubiyya Mosque in Marrakech, from the mid-12th century, are cited by the historian Jonathan Bloom as the earliest reliably dated example in Morocco.
How it works
Tiles are first made as glazed squares, typically about 10 centimeters on a side. A craftsman draws the shape on the glaze and cuts it by hand with a sharp, adze-like hammer, then bevels the edges. The cut pieces, in different colors, are laid face down on the ground and fitted together like a puzzle with the finest possible joints. Mortar is poured over the back to fix them into a panel, which is then raised and set on the wall.
How it spread
Under the Almoravids, Almohads and Marinids the art was enriched across Morocco and al-Andalus. By the 14th and 15th centuries tile mosaic made of many small hand-cut pieces covered famous buildings of the region: the Alhambra palaces in Granada, the mosques of Tlemcen and the Marinid madrasas of Fez, Meknes and Sale. Blue, green and yellow joined the earlier palette, and red was added in the 17th century.
Where it stands today
After the 15th century traditional mosaic zellij fell out of fashion in most countries except Morocco, where it continues to be produced. Fez remains a center of production, and in Tetouan the tiles are cut to shape before firing. The Hassan II Mosque in Casablanca, inaugurated in 1993, was decorated with zellij made in this way.
