The Imperial Library of Constantinople, in the capital city of the Byzantine Empire, was the last of the great libraries of the ancient world. Long after the destruction of the Great Library of Alexandria and the other ancient libraries, it preserved the knowledge of the ancient Greeks and Romans for almost 1,000 years. A series of unintentional fires over the years and wartime damage, including the raids of the Fourth Crusade in 1204, impacted the building itself and its contents. The library continued in substantial form until the city of Constantinople was conquered by the Ottoman Empire on 29 May 1453 when the library's considerable surviving contents were destroyed or lost. The library was founded by Constantius II (reigned 337–361 AD) who established a Scriptorium so that the surviving works of Greek literature could be copied for preservation. The Emperor Valens in 372 employed four Greek and three Latin calligraphers. The majority of Greek classics known today are known through Byzantine copies originating from the Imperial Library of Constantinople.
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