Estimates vary; somewhere between 40,000 and 400,000 scrolls, perhaps equivalent to roughly 100,000 books
Estimated to have employed over 100 scholars at its height
The Great Library of Alexandria in Alexandria, Egypt, was one of the largest and most significant libraries of the ancient world. The Library was part of a larger research institution called the Mouseion, which was dedicated to the Muses, the nine goddesses of the arts. The idea of a universal library in Alexandria may have been proposed by Demetrius of Phalerum, an exiled Athenian statesman living in Alexandria, to Ptolemy I Soter, who may have established plans for the Library, but the Library itself was probably not built until the reign of his son Ptolemy II Philadelphus. The Library quickly acquired a large number of papyrusscrolls, due largely to the Ptolemaic kings' aggressive and well-funded policies for procuring texts. It is unknown precisely how many such scrolls were housed at any given time, but estimates range from 40,000 to 400,000 at its height.
Despite the widespread modern belief that the Library was burned once and cataclysmically destroyed, the Library actually declined gradually over the course of several centuries, starting with the purging of intellectuals from Alexandria in 145 BC during the reign of Ptolemy VIII Physcon, which resulted in Aristarchus of Samothrace, the head librarian, resigning from his position and exiling himself to Cyprus. Many other scholars, including Dionysius Thrax and Apollodorus of Athens, fled to other cities, where they continued teaching and conducting scholarship. The Library, or part of its collection, was accidentally burned by Julius Caesar during his civil war in 48 BC, but it is unclear how much was actually destroyed and it seems to have either survived or been rebuilt shortly thereafter; the geographer Strabo mentions having visited the Mouseion in around 20 BC and the prodigious scholarly output of Didymus Chalcenterus in Alexandria from this period indicates that he had access to at least some of the Library's resources.
The Library dwindled during the Roman Period, due to lack of funding and support. Its membership appears to have ceased by the 260s AD. Between 270 and 275 AD, the city of Alexandria saw a rebellion and an imperial counterattack that probably destroyed whatever remained of the Library, if it still existed at that time. The daughter library of the Serapeum may have survived after the main Library's destruction. The Serapeum was vandalized and demolished in 391 AD under a decree issued by Coptic ChristianPope Theophilus of Alexandria, but it does not seem to have housed books at the time and was mainly used as a gathering place for Neoplatonist philosophers following the teachings of Iamblichus.
The Library of Alexandria was not the first library of its kind. A long tradition of libraries existed in both Greece and in the ancient Near East. The earliest recorded archive of written materials comes from the ancient Sumerian city-state of Uruk in around 3400 BC, when writing had only just begun to develop. Scholarly curation of literary texts began in around 2500 BC. The later kingdoms and empires of the ancient Near East had long traditions of book collecting. The ancient Hittites and Assyrians had massive archives containing records written in many different languages. The most famous library of the ancient Near East was the Library of Ashurbanipal in Nineveh, founded in the seventh century BC by the Assyrian king Ashurbanipal (ruled 668–c. 627 BC). A large library also existed in Babylon during the reign of Nebuchadnezzar II (c. 605–c. 562 BC). In Greece, the Athenian tyrant Peisistratos was said to have founded the first major public library in the sixth century BC. It was out of this mixed heritage of both Greek and Near Eastern book collections that the idea for the Library of Alexandria was born.
The Macedonian kings who succeeded Alexander the Great as rulers of the Near East wanted to promote Hellenistic culture and learning throughout the known world. Historian Roy MacLeod calls this "a programme of cultural imperialism". These rulers therefore had a vested interest to collect and compile information from both the Greeks and from the far more ancient kingdoms of the Near East. Libraries enhanced a city's prestige, attracted scholars, and provided practical assistance in matters of ruling and governing the kingdom. Eventually, for these reasons, every major Hellenistic urban center would have a royal library. The Library of Alexandria, however, was unprecedented due to the scope and scale of the Ptolemies' ambitions; unlike their predecessors and contemporaries, the Ptolemies wanted to produce a repository of all knowledge.