It's hard to tell when mosaics first come onto the scene. After all, decoration by arranging different colored stones is a fairly obvious pursuit. This page asserts:
"The history of mosaic goes back some 4,000 years or more, with the use of terracotta cones pushed point-first into a background to give decoration."
By the 4th century BC mosaic floors were starting to be common in Hellenistic and Roman villas. The largest collection of late Roman mosaics are said to be found in Sicily, at the Villa Romana del Casale, the most famous being in the "room with girls in bikinis."
By the second century bc, tesserae--small, colorful tiles--began to be manufactured, giving mosaic artists a wider pallet so that mosaic works could be more representative. The small tesserae meant that in the right hands details could be produced that could imitate paintings. Since the tesserae were durable, the works could last a very long time.
After the Romans spread mosaics, it was the rise of the Byzantine Empire from in the 5th century onward that made mosaic works even more popular. Availability of the glass tesserae (sometimes backed in gold or silver) known as smalti, manufactured in northern Italy cities like Venice, gave the mosaic artist an extraordinary range of options and the art flourished.
By the 8th century, the Muslim world also gets involved in producing mostly geometric designs using mosaic tiles of ceramic, glass or stone, which can be seen in the Great Mosque at Cordoba and the Alhambra Palace.
In our time, the Art Deco period revived interest in mosaics. Notable among the users of mosaics, especially to recycle broken ceramic, was Antoni Gaudí.
Where to See Mosaics in Europe
Ravenna - well-known for its mosaics, Ravenna has a number of sites with mosaic art. My favorite is Mausoleo di Galla Placidia
Venice - The glittering mosaics of St Mark's have been calculated to cover an area of about an acre.
Sicily - Villa Romana del Casale
Barcelona - Antoni Gaudí's Parque Güell and mosaic work is still going on at La Sagrada Familia.
Cordoba - The Great Mosque
Granada - The Alhambra Palace
Conimbriga, Portugal - See the Roman pictorial mosaics in the House of the Fountains.
