The Abbasid Caliphate, established in 750 CE after the overthrow of the Umayyads, shifted the center of the Muslim world eastward with the founding of Baghdad as its capital in 762 CE under Caliph al-Mansur. The Abbasid era, especially from the eighth through the thirteenth centuries, is often called the Islamic Golden Age, a period of remarkable intellectual and scientific achievement. Central to this flourishing was the Bayt al-Hikmah, or House of Wisdom, a Baghdad institution that reached its height under Caliph al-Ma'mun in the early ninth century. There, scholars of diverse backgrounds, including Muslims, Christians, Jews, and Sabians, translated Greek, Persian, and Indian scientific and philosophical texts into Arabic, preserving works that might otherwise have been lost and expanding on them with original research. This translation movement advanced mathematics, astronomy, medicine, optics, and philosophy, associated with figures such as al-Khwarizmi, whose work gave rise to the term "algebra," and al-Kindi, an early Islamic philosopher. Baghdad became one of the largest and most intellectually vibrant cities in the world, and its scholarly networks later helped transmit this knowledge to medieval Europe. Abbasid political power gradually declined after the tenth century and the caliphate effectively ended when the Mongols sacked Baghdad in 1258 CE.
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