A short history of the Library of Alexandria
The Library is founded by Ptolemy, and the person put at the head is chosen by Aristotle (Alexander's tutor), he chooses Demetrius of Phalerum. It starts off Aristocratic (Class based rather than propositions of a whole) under Aristotle, so it becomes a tyrannical pursuit for knowledge, confiscating books, fueding with other libraries, and with no actual function for the collected books.
The books are then catalogued and organized some time later. The Library becomes more of what it was meant to be and several things are discovered and invented there, the whole city becomes advanced and Hydraulics are invented along with several other things including the Steam Engine, but they did not realize the scalability.
Then Rome has a Civil war between Ceasar and Pompey, and the Alexandrians kill Pompey when he comes. Ceasar comes a few days later and comes with a show of strength and it starts a riot, where the Romans are forced into the palace and eventually set fire to the ships in the harbor to take control and escape.
100 years later it is investigated and thought that around 400,000 books were burned in the fire. When the Christians take power a Mathematicians daughter has a following in Alexandria, but she is Pagan and influencing the leader so they skin her with Oyster shells and kill her. When the Muslims come they ask a Librarian what they have there and he tells them there are 40,000 priceless works, and they say if it is in line with the word of God they don't need it, and if it is not then it ought be destroyed. So it is said it was commanded that the Library be used to fuel the fires to heat the bath houses.
Long version here: