House of Wisdom
Today in 763 (or possibly in 766), Harun al-Rashid was born. He was the fifth Abbasid caliph, reigning from September 786 until his death in March 809, ruling an empire reaching from the western Mediterranean to India
Harun established the legendary library Bayt al-Hikma ("House of Wisdom") in Baghdad in present-day Iraq, and during his rule Baghdad began to flourish as a world center of knowledge, culture and trade.
Encyclopedia Britannica:
The scholarly splendour of the Islamic world from the 8th to the 13th century can in large part be attributed to the maintenance of public and private book libraries. The Bayt al-Ḥikmah (“House of Wisdom”), founded in 830 in Baghdad [under al-Rashid’s son, al-Ma'mun, who expanded it into a thriving learning center], contained a public library with a large collection of materials on a wide range of subjects, and the 10th-century library of Caliph al-Ḥakam in Cordova, Spain, boasted more than 400,000 books.
Matthew Battles in Library: An Unquiet History:
The House of Wisdom was a center of translation, compilation, and comparison of the wisdom of the peoples under Muslim rule from India to the Iberian peninsula. The Arabic translator of Euclid, al-Hajjaj, worked there alongside al-Khwarizmi, inventor of algebra, from whose name we take the word “algorithm.” Reading Hindu mathematical treatises collected in the library at the House of Wisdom, al-Khwarizmi adapted the Hindu numbering system to suit his own purposes, giving birth to the Arabic numerals we use today.