The event that made the great schism forever permanent was the
third crusade
fall of rome
fourth crusade
fifth crusade

The Great Schism of 1054 was the break of communication between what are now Eastern Orthodox and Roman Catholic churches. The Fourth Crusade was a Western European armed expedition which was intended to conquer Jerusalem. On their way to Holy land, the crusaders reached Constantinople in 1203. In February 1204 the crusaders and Venetians ( under their Doge Dandolo ) decided to capture the city of Constantinople. They brutally sacked the city and their leaders established the Latin Empire on lands captured from the Byzantine Empire. C ) Fourth Crusade.

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