<P> The migration waves of Byzantine scholars and émigrés in the period following the Crusader sacking of Constantinople and the end of the Byzantine Empire in 1453, is considered by many scholars key to the revival of Greek and Roman studies that led to the development of the Renaissance humanism and science . These emigres were grammarians, humanists, poets, writers, printers, lecturers, musicians, astronomers, architects, academics, artists, scribes, philosophers, scientists, politicians and theologians . They brought to Western Europe the relatively well - preserved remnants and accumulated knowledge of their own (Greek) civilization, which had mostly not survived the Dark Ages in the West . </P> <P> Their main role within the Renaissance humanism was the teaching of the Greek language to their western counterparts in universities or privately together with the spread of ancient texts . Their forerunners were Barlaam of Calabria (Bernardo Massari) and Leonzio Pilato, both drawn from culturally Byzantine Calabria in southern Italy . The impact of these two scholars on the very first Renaissance humanists was indisputable . </P>

What happened in europe to help spark the renaissance
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