Al-Andalus was Muslim-ruled Iberia, from the conquest of 711 to the fall of Granada in 1492 — for three centuries the wealthiest and most learned society in western Europe.
Al-Andalus is the name Arabic sources give to the parts of the Iberian peninsula under Muslim rule, from the conquest that began in 711 to the surrender of Granada in 1492 — seven hundred and eighty-one years, though the territory at the end was a fraction of the territory at the start.
For roughly its first three centuries it was the most economically advanced and intellectually productive society in western Europe. Córdoba in the tenth century had paved and lit streets, running water, hospitals and a library said to hold hundreds of thousands of volumes, at a time when the largest cities of Latin Christendom held a few thousand people.
It is also the region this archive returns to most often, because the Reconquista, the Almoravids, the Almohads, the military orders and half the Iberian kingdoms are all defined against it.
In 711 a force under Tariq ibn Ziyad crossed from North Africa and destroyed the Visigothic king Roderic at the Guadalete. The Visigothic kingdom collapsed with a speed that has been argued about ever since — it had been weakened by succession disputes, and substantial parts of its nobility came to terms rather than fight.
Within a decade almost the whole peninsula was under Muslim control, and raiding parties had crossed the Pyrenees into Frankish Gaul. The advance north was checked near Tours in 732, and the frontier settled along the Duero and the Ebro.
What remained Christian was the mountainous north — Asturias, and later León, Navarre, Aragon and the Catalan counties. The Battle of Covadonga, traditionally dated to 722, is where later Christian tradition placed the beginning of the Reconquista, though it was a small engagement enlarged by hindsight.
When the Abbasids destroyed the Umayyad dynasty in Syria in 750, one prince escaped: Abd al-Rahman I reached Iberia in 756 and made himself emir of Córdoba, founding a state independent of Baghdad in fact if not in theory.
His descendants ruled for two and a half centuries. In 929 Abd al-Rahman III took the title of caliph outright, in direct challenge to both Baghdad and the Fatimids of Egypt, and built the palace-city of Madinat al-Zahra outside Córdoba as its expression.
The tenth-century caliphate is the high point. Christian kings in the north paid tribute, embassies came from Constantinople and the German emperors, and the state ran on a professional army, a gold coinage and an agricultural system transformed by irrigation techniques and crops — citrus, rice, sugar cane, cotton — brought from the eastern Islamic world.
Al-Andalus is the principal route by which Greek philosophy and science reached Latin Europe, and this is not a small claim about a cultural ornament — it is most of the intellectual history of the twelfth century.
Ibn Rushd, known in Latin as Averroes, wrote the commentaries on Aristotle that shaped scholastic philosophy for three centuries; Maimonides, born in Córdoba, is the central figure of medieval Jewish thought; al-Zahrawi's surgical encyclopaedia was used in European medicine into the eighteenth century.
The transmission ran largely through Toledo after its capture in 1085, where Arabic and Hebrew texts were translated into Latin by teams of Christian, Jewish and Muslim scholars. The convenient word for the coexistence that made this possible is convivencia, and it should be used carefully: the relationship between the three communities ranged from genuine collaboration to legal subordination to episodes of massacre, and it varied by century and by ruler.
The caliphate destroyed itself. A succession crisis after 1009 became a civil war, and in 1031 the caliphate was formally abolished, leaving perhaps thirty independent principalities — the taifa kingdoms — at Seville, Zaragoza, Toledo, Granada, Badajoz and elsewhere.
They were militarily feeble and culturally brilliant: the taifa courts competed in poetry and patronage while paying protection money, the parias, to the Christian kings in the north. That tribute is what funded the expansion of León-Castile, and it is the mechanism by which the balance of the peninsula reversed.
It was also unsustainable. When Alfonso VI took Toledo in 1085 — the old Visigothic capital, and a shock to the whole Muslim world — the taifa rulers appealed to North Africa for help.
The Almoravids came from Morocco in 1086, beat Alfonso VI at Sagrajas, and then annexed the taifa kingdoms they had come to rescue. The Almohads replaced them from the 1140s and did the same thing again, defeating Castile heavily at Alarcos in 1195.
Both were reforming Berber movements from the Maghreb, and both regarded the Andalusi elite as decadent. The intellectual life of al-Andalus continued under them — Averroes served the Almohad caliphs — but the political independence of Muslim Iberia did not survive its rescuers.
The reversal came at Las Navas de Tolosa in 1212, where a coalition of Castile, Aragon and Navarre destroyed the Almohad army. Within forty years Córdoba, Seville and Valencia had all fallen.