In ancient times, Seville used to be called Hispalis and, while under Roman power, Romulensis. In 590 and 619 A.D., Seville was the venue of two councils (concilia Hispalensia). The Arabs conquered the city in 712 and made it the capital of the province of Išbīliya ( إشبيلية ), which is the root of the city's name Sevilla today. In 844 the Normans destroyed the city. After the overthrow of the caliphate of Cordoba, Seville established itself within the taifa principalities and it became the seat of the Abbadids. This signaled a start into an era of glamour for the city. In 1091, Seville fell into the hands of the berberic Almoravides, who were displaced by the Almohades. On November 22, 1248, the city was conquered by Ferdinand III. of Castilla after a month long siege. From then on it stayed in the possession of the Christian Spaniards. The second era of splendor arrived in the 16th and 17th century, when Seville became the trans-shipment center of the Spanish maritime trade and the focal point of Spanish art, especially its painters. But the industriousness decreased with time, when about 300,000 Moors emigrated gradually into the Muslim areas of Granada and Northern Africa. Slowly Seville lost its eminent position in the trade between with America to the aspiring port of Cadiz. Seville saw the signing of a 1729 friendship and peace agreement between Spain, France, and England, which the Netherlands joined later on. In 1929 and 1992, Seville was the venue of the World Expo. The Spanish architect Santiago Calatrava designed the Alamillo Bridge for the 1992 event, while the impressive Plaza de Espana was built on the edge of the Maria Luisa Park in 1929.