The Lost Libraries:
* During the Hellenistic Period (323-31BC) there were several major libraries in the Mediterranean world, the greatest being the Library of Alexandria, established about 300BC – it was damaged in 48BC and probably destroyed in the reign of the Roman Emperor Aurelian (270-275AD).
* Alexandria’s closest rival was the library at Pergamum, a Greek city in what is now Turkey. The library at Pergamum was said to house over 200,000 works of history, literature, poetry and more. The precise fate of the contents of the library are unknown. One version has it that Mark Antony gave all of the works to Cleopatra for the Library of Alexandria as a wedding present. Another version suggests that Mark Antony sent the collection at Pergamum to Cleopatra as a reimbursement for the destruction of the Library of Alexandria by Julius Caesar. We will probably never know the exact fate of these works, but, suffice it to say, they have been lost.
* The Roman conquest of the kingdom of Macedon in 168 BC led to the seizure of its imperial library, which was taken to Rome.
* During the Roman Empire, major libraries were built in Rome, often with separate buildings to hold Latin and Greek works – a catalogue of Rome’s buildings from c. 350AD, 60 years before the city was burnt and looted by the Visigoths, lists 29 public libraries in the city, all now lost.
Lost works:
We have perhaps only some 10% of the major works of classical literature, according to Professor Robert Fowler with Bristol University, an expert on ancient literature. Most works in most genres have been lost.
A representative sample of these losses includes:
Aeschylus – only 7 of his 80 plays survive
Aristophanes – 11 out of 40 plays survive
Ennius – his epic poem Annales, is almost entirely lost
Euripides – 18 of his 90 plays survive
Livy – three-quarters of his History of Rome are lost
Sappho – most of her nine books of lyric poems are lost
Sophocles – only 7 entire plays survive of 120 he wrote
The Velvet Rocket 
What a shame.
All of that lost history. Historical documents. Early scientific knowledge. Books of the ancient philosophers.
As to the Library of Alexandria, I read somewhere that after the main library was fully destroyed, ancient scholars used a “daughter library” in a temple known as the Serapeum, located in another part of the city. According to Socrates of Constantinople, Coptic Pope Theophilus destroyed the Serapeum.
Other examples include:
Qin Shi Huang, first emperor of Qin Dynasty, ordered a Burning of books and burying of scholars in 213 BC and burial alive of 460 Confucian scholars in 210 BC in order to stay in the throne. Some of these books were written in Shang Xiang, a superior school founded in 2208 BC. The event caused the loss of many philosophical treatises of the Hundred Schools of Thought.
After the First Council of Nicea (CE 325), Roman emperor Constantine the Great issued an edict against nontrinitarian Arians which included systematical book burning.
According to the Chronicle of Fredegar, Recared, King of the Wisigoths (reigned 586–601) and first Catholic king of Spain, following his conversion to Catholicism in 587, ordered that all Arian books should be collected and burned; and all the books of Arian theology were reduced to ashes, with the house in which they had been purposely collected.
During the conquest of the Americas and the aftermath of the encounter between European and indigenous American civilizations, many books written by indigenous peoples were destroyed. There were many books in existence at the time of the Spanish conquest of Yucatán in the 16th century, however most were destroyed by the Conquistadors and Catholic priests. In particular, many in Yucatán were ordered destroyed by Bishop Diego de Landa in July of 1562. De Landa wrote: “We found a large number of books in these characters and, as they contained nothing in which were not to be seen as superstition and lies of the devil, we burned them all, which they (the Maya) regretted to an amazing degree, and which caused them much affliction.”
And the destruction of Library of Nalanda in India in the 12th Century.
An excellent source of the list of the major libraries worldwide that have been destroyed is at the chart located here:
https://en.wikipedia.org/wiki/List_of_destroyed_libraries
It’s really a miracle, given the destructive tendencies of zealots and the ravages of time, that so much survived from antiquity. How many of the documents created on digital media in the 21st century will be accessible a hundred years later, not to mention in a couple of millennia?
Jim: It helps that “zealots” more often spent their time COPYING ancient books.
Makes one want to copy the world’s literature on asbestos paper, but of course that would be declared a hazardous material and put in a hazmat dump immediately.