Sometime in the early 1140s a scholar from northern Italy made an arduous crossing of the Alps and the Pyrenees and eventually arrived in the newly reconquered Spanish town of Toledo. There Gerard of Cremona was given the position of canon at the cathedral, formerly the Friday Mosque, which had recently been seized from the town’s Muslims.
Before the rise of Islam, Toledo had been the capital city of Visigothic Spain, and its capture by Alfonso VI of Castile was an important moment in the Christian reconquista of the land known to Islam as al-Andalus. Many of the Muslims of the city had, however, chosen to stay on under Castilian rule, and among them was a scholar named Ghalib the Mozarab. It is not known how Gerard and Ghalib met and became friends, but soon after Gerard’s arrival the two began to cooperate on a series of translations from Toledo’s Arabic library, which had survived the looting of the conquering Christians.
As Richard Fletcher points out in The Cross and the Crescent: Christianity and Islam from Muhammad to the Reformation, Gerard and Ghalib’s mode of translation was not one that would be regarded as ideal by modern scholars. Ghalib rendered the classical Arabic of the texts into Castilian Spanish, which Gerard then translated into Latin. Since many of the texts were Greek classics that had themselves arrived in Arabic via Syriac, there was much room for error. But the system seems to have worked. In the course of the next half-century, Ghalib and Gerard translated no fewer than eighty-eight Arabic works of astronomy, mathematics, medicine, philosophy, and logic, branches of learning that underpinned the great revival of scholarship in Europe sometimes referred to as the Twelfth-Century Renaissance.
Other translations from the Arabic during this period filled European libraries with a richness of learning impossible even to imagine a century before: they included editions of Aristotle, Euclid, Plato, and Ptolemy, commentaries by Avicenna (Ibn Sina), and astrological texts by al-Khwarizmi, encyclopedias of astronomy, illustrated accounts of chess, and guides to precious stones and their medicinal qualities.
It was a crucial but sometimes forgotten moment in the development of Western civilization: the revival of medieval European learning by a wholesale transfusion of scholarship from the Islamic world. It was probably through Islamic Spain that such basic facets of Western civilization as paper, ideas of courtly love, algebra, and the abacus passed into Europe. Meanwhile the pointed arch and Greco-Arab (or Unani, from the Arabic word for Greek/Ionian) medicine arrived in Christendom by way of Salerno and Sicily, where the Norman king Roger II—known as the “Baptized Sultan”—was commissioning the Tunisian scholar al-Idrisi to produce an encyclopedic work of geography.
Some scholars go further. Professor George Makdisi of Harvard has argued convincingly for a major Islamic contribution to the emergence of the first universities in the medieval West, showing how terms such as having “fellows” holding a “chair,” or students “reading” a subject and obtaining “degrees …