The "Islamic Golden Age" was a period in which Greek and Roman works of philosophy and proto-science were translated copied and studied and these disciplines were expanded on by Arabic scholars from Spain to Baghdad. Arabic-speaking scholars analysed and synthesised ancient Greek knowledge, assimilated it into Islamic thought and significantly developed it. As a result, they advanced knowledge in mathematics, chemistry, physics, optics, medicine and many other disciplines. This period of rich Arabic scholarship truly began in the period of the Abbasid Caliphate, c. 750 AD, but declined in the twelfth and thirteenth centuries. By that stage medieval Europe was beginning to take a leading role in the advancement of knowledge in these disciplines and to lay the foundations of the later Scientific Revolution.
The reasons for the decline of the Islamic Golden Age is partially found in the reasons for its rise. As Islam expanded it conquered the Persian Empire and parts of the Eastern Roman Empire. In the process it absorbed some of the ancient world's most significant centres of learning. In the eastern Mediterranean the scholarly centres of Alexandria and Antioch came under Islamic control. In the east the Nestorian Christian schools of Nisibis and Edessa and the Persian scholarly centre of Gondishapur continued to be centres of learning under Muslim rule. The Nestorian schools in particular were major conduits of ancient Greek learning, since many Greek works, which at around this time were being lost in the collapse of the Western Roman Empire and its aftermath, were preserved by the Nestorians in Syriac translation and so found their way into Arabic.