Final answer:
The Fourth Crusade diverges from earlier crusades due to its shifted focus from reclaiming Christian lands from Muslim rule to addressing internal Byzantine issues and the unintended diversion to Zadar due to unpaid debts. This change in objectives made it distinct from the earlier crusades.
Step-by-step explanation:
The Fourth Crusade is distinct from its predecessors primarily due to its radically different mission. Early crusades, like the First Crusade, aimed to expel Muslim rulers from previously Christian lands. These endeavours culminated in the creation of four Christian-ruled states in places like Palestine and Syria. However, the Fourth Crusade had diverged from this path, shifting their focus to addressing supposed moral wrongs within the Byzantine Empire's inner workings.
During the First Crusade, Christian control was reinstated over significant portions of Palestine and Syria. Despite later attempts to reestablish their dominance in further crusades, Christians could not regain full control over crucial religious sites like Jerusalem. However, the goal of the Fourth crusade was to restore a legitimate ruler to the Byzantine Empire, a mission accomplished in the spring of 1204. This drastic change in the objective differentiated the Fourth Crusade from the previous crusades.
Due to outstanding debts, the destination of the Fourth Crusader was also deviated to the city of Zadar (or 'Zara') at the insistence of Venetian merchants, before the original goal could be pursued. This decision was made regardless of the Pope's opposition and despite Zadar being a Catholic city, which further solidified the uniqueness of the Fourth Crusade.
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