Q
Hard 1 Mark
Islamic Studies Caliphate & Rulers: From the Rightly Guided Caliphs to the Ottoman Caliphate
What happened to the books of the House of Wisdom when Baghdad fell?
Explanation
When Hulagu Khan destroyed Baghdad, the books of the House of Wisdom were thrown into the Tigris River — it is said the water turned black from the ink.
Reference: Islamic Studies - Caliphate & Rulers , Page 8
Hint
This was one of history's greatest intellectual destructions.