Final answer:
The Crusades were a series of religious wars between Christians and Muslims in the Middle Ages. Causes included religious, political, and economic motivations. Italian city-states benefited from the Crusades through trade and control of the Mediterranean.
Step-by-step explanation:
The Crusades were a series of religious wars fought between Christians and Muslims in the Middle Ages. There were multiple causes for the Crusades, including religious zeal, the desire to recapture the Holy Land, and political and economic motivations. Some of the key beneficiaries of the Crusades were the Italian city-states, as they gained wealth and power through trade and control of the Mediterranean.
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