Islamic Golden Age
The Islamic Golden Age is traditionally understood to have begun during the reign of the Abbasid caliph Harun al-Rashid (786 to 809) with the inauguration of the House of Wisdom, which saw scholars from all over the Muslim world flock to Baghdad, the world's largest city by then, to translate the known world's classical knowledge into Arabic and Persian.  Under the Umayyads, Al-Andalus also became a centre of science, medicine, philosophy and invention during the Islamic Golden Age.