Quoted from T. Glick: The Dictionary of the Middle Ages; vol. 11; J.R. Strayer, Editor in Chief; Charles Scribner’s Sons, N. York; pages 213-214.
[Seville is a] Spanish city located on a meander of the Guadalquivir River, ninety-seven kilometers (sixty miles) from the Atlantic coast at Cadiz. Known as Ishbilya in Arabic, Seville was second to Cordoba in size and importance throughout most of the Islamic period, reaching its maximum extension of 187 hectares (462 acres) and its greatest population (83,000) in the mid twelfth century, when the city was favoured by Almohad dynasts.
Until the ninth century, the city was confined to the limits of the primitive Roman oppidum (town). After the sack of the city by Norman pirates in 844, the Umayyad emir Abd al-Rahman II ordered the reconstruction of the walls to include both the old city and the newer suburbs to its east and north. The walls were rebuilt in the early tenth century and again a century later. Finally, in 1170-1171 the Almohad caliph Abu Ya'qub Yusuf, who made Seville his capital, rebuilt the portion of the wall adjacent to the river, after a calamitous flood. The Alcazar, or citadel, originally built by Abd al-Rahman II, was restored by the Almohads, who were likewise responsible for building a new main mosque (1172-1176), of which only the minaret, now called the Giralda, still remains. At the time of the conquest of the city by Ferdinand III of Castile (1248), Seville boasted seventy-two mosques.
After the fall of the Umayyad caliphate in Seville (1013), the chief religious judge (qadi), Abu'l- Qasim ibn Abbad, proclaimed himself ruler (hajib) of an independent Sevillian principality that lasted until the Almoravid conquest of 1091. Its greatest ruler, al-Muqtadid (r. 1042-1069), both enlarged the kingdom and wrote poems praising the city's undoubted grandeur during this period.
The Almohads, in building a new main mosque near the river, to the south of the old urban centre, created a dual economic zonation whereby the export and local economic activities were each confined to specific areas. The Alcaicera, or covered market, where expensive silks were sold for export, was located near the riverine port.
The Alhondiga, or flour exchange, supplying the needs of the townspeople was in the centre of town, near the previous main mosque. Islamic Seville was a centre for the trade, both domestic and overseas, of the olive oil produced in the nearby Aljarafe region. A picture of the economic life of Almohad Seville is preserved in the market regulation, or hisba, treatise of ibn'Abdun, which describes not only a great variety of alimentary trades but also construction, textile, and iron industries.
The city had received its domestic water supply from an arched aqueduct of Roman construction, known in the later Middle Ages as the Canos de Carmona. By the twelfth century this system had fallen into disrepair, but it was restored by the Almohad rulers in 1172. The Castilians encountered the system still functioning, and in 1254 Alfonso X ordered a ''Master Caxico" (probably a resident Genoese) to "make the water [of the Carmona aqueduct] flow to two fountains in Seville as it used to flow in the time of the Moors." The Almohads, when building their new main mosque, uncovered the Roman sewer system and altered and enlarged its course.
When the Castillan army captured the city in 1248, most of the Muslim population fled and was replaced by settlers of predominantly Castilian origin. The mosques were granted as churches or houses, with three reserved as synagogues for the Jewish population. The Christian conquest resulted in a severe depopulation of the city, as the displacement of the Muslim residents created many open spaces separating Christian neighbourhoods with relatively low population densities. Low-density areas on the urban periphery, adjacent to the walls, tended to attract monastic establishments. The Jewish quarter occupied approximately 11 percent of the walled city; hence the density of Jewish settlement, up to the pogrom of 1391, must have been substantially greater than that of the Christian population. A small Muslim quarter, housing mainly artisans (masons, weavers, and smiths, in particular), also subsisted after the Christian conquest. Post conquest society was characterized by an urban aristocracy whose wealth was based in rural properties, particularly in the Aljarafe district, and by a large number of free burghers, or francos, who were prominent in the textile industry and in local commerce. Overseas trade was in the hands Genoese (who had been established in the city since Almohad times as merchants, armourers, and bankers), Florentines, and Castilians. These groups dominated the export trade in wheat, olive oil, hides, and other agricultural products, which turn dominated the overseas commerce.
The functional separation of the city into two distinct economic zones survived unchanged from Almohad times. International trade was centred near the river in the Barrio de la Mar (in fact, separate jurisdictional entity) and in the so-called Genoese and Castilian quarters, where the Genoese and textile exchanges (Lonja de Genova, Lonja de los Panos) were located, along with the covered market and olive-oil warehouses. The economic life of the city proper continued to be located nearer the city's centre.
by: Quoted from T. Glick, Sat 20 July, 2002