The Cathedral of Monreale ("Santa Maria la Nuova,") in Monreale, Sicily, was begun about 1170 by William II, one of the Norman kings in northern Sicily. In 1182 the church, dedicated to the Assumption of the Virgin Mary, was, by a bull of Pope Lucius III, elevated to the rank of a metropolitan cathedral.
The mosaics of Monreale's duomo are grandiose, covering practically every inch of the vast interior. They extend to 6,500 m² or 68,220 square feet of glittering gold mosaics. It is the largest cycle of Byzantine mosaics in Italy.
Completed in 1182, the rich mosaic cycle adorning the walls shows scenes from the Old Testament (nave), Teachings of Christ (aisles, choir, and transepts), and the Gospels (side apses).
The design, execution and choice of subjects all appear to be of Byzantine origin, the subjects being selected from the Menologium drawn up by the emperor Basil II in the 10th century.
The cathedral's Latin-cross plan focuses on the imposing mosaic of Christ Pantocrator (the all-powerful Christ), which dates from the 12th or 13th century. The Byzantine mosaic decorations were executed by skilled Venetian and Moslem craftsmen.