Final answer:
The greatest successes of the Second, Third, and Fourth Crusades were the recapture of Edessa, an alliance between the Crusader state rulers and Saladin, and the conquest of Jerusalem.
Step-by-step explanation:
The greatest success achieved during the Second Crusade was the recapture of Edessa, which had been captured by the Muslims. However, overall the Second Crusade did not achieve significant successes.
The Third Crusade was marked by an alliance between the Crusader state rulers and Saladin against common enemies. This strategic alliance led to a period of relative peace and stability in the region.
The conquest of Jerusalem was the greatest success of the Fourth Crusade. The Crusaders managed to capture the city, establishing Christian control over Jerusalem for a period of time.
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