The Great Schism of 1378 differed from the one in 1054 because

The Great Schism of 1378 began when rival groups supported different men as pope, creating a struggle over who held power in the papacy. The schism of 1054, by contrast, was the lasting split between the Roman Catholic Church in the West and the Eastern Orthodox Church. So the 1378 schism was based on a power struggle, not a division between eastern and western churches.

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