MACIAS, Santiago - Mosaicos de Mértola: arte bizantina no ocidente mediterrânico. Mértola: Câmara Municipal, 2011. [43] p. ISBN 978-989-95873-5-9
A full explanation for such an unusual and luxurious project lies in the mining wealth of the region and the seizure of power in the city by a merchant class that took upon itself the management of these resources. The importance of eastern communities in southern cities should also be stressed. In this regard, epigraphy has given us an invaluable contribution, allowing us to establish links between Mértola and groups of merchants who used Greek as a language of communication. The relations between Mértola and the Byzantine world would have increased by these contacts, including the city in the circuit of artistic production of the time. The path travelled from East to West by the mosaic artisans who worked in the religious complex of the palatial area would not have been possible without such an environment of contacts and relationships. Most of all, none of this would have been possible without the impulse of trade and the decisive role of merchants.