The Fall of Constantinople to the Ottoman Empire in 1453 marked the end of the Roman Empire, and it caused Greek scholars and other intellectuals to migrate to Italy to help revive the Italian Renaissance. Their roles were: grammarians, humanists, poets, writers, printers, lecturers, musicians, astronomers, architects, academics, artists, scribes, philosophers, scientists, politicians and theologians. They brought to Europe the far greater preserved and accumulated knowledge of their own Greek civilization.

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