During the Abbasid-era in Baghdad, Iraq there was a library and translation institution known as the House of Wisdom. This was a key part of the global translation movement at the time and was known as the hub of intellectual and technical advancement during the Islamic Golden Age.
For centuries it stood as an unrivaled pillar of knowledge and learning, developing the studies of humanities and science. The library contained hundreds of manuscripts that covered all range of subjects like mathematics, astronomy, medicine, alchemy, and chemistry. There were even drawings on Persian, Indian and Greek texts: including scripts from some of the greatest philosophers to ever walk the earth.
It is thought to have contained a complete series of texts written by Pythagoras, Plato, Aristotle, Hippocrates and even Galen or Charaka. Amazingly, these texts were translated into numerous languages, it was a time in Islamic history were learning and discoveries were cherished. The scholars part of this library created an immense collection of world knowledge, which was used to build on and further their learning with their own discoveries.
Unfortunately, it was never to last, along with every library in Baghdad, the House Of Wisdom was completely destroyed during the Mongol invasion in 1258. The Mongols were a very dangerous East-Central Asian ethnic group that’s culture thrived on conquest, simply put they had little to give to the world in terms of trade so they banded together to conquer surrounding countries.
It is said that when they destroyed the House Of Wisdom, the river Tigris ran black for six months due to the huge amount of books they destroyed: the black ink discolored the river for months. Scholars believe the amount of knowledge that was destroyed and lost is indescribable, setting the world back by decades possibly.
The surprising thing is that while many people know about the destruction of the library of Alexandria, barely anyone knows about the destruction of the House of Wisdom.