Icons are religious images that are immensely valuable in Christian traditions. The schism between Rome and Constantinople was over such images. Iconoclasts were people who were against icons because they thought they were replacing God and were representative of idolatry. The issue grew so intense that a second pope was raised in Constantinople, and the pope in Constantinople and the pope in Rome excommunicated each other. This led to the split between the Roman Catholic Church and the Eastern Orthodox Church.
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