The exchange of new ideas and inventions made throughout the Crusades is considered the earliest beginning of the Renaissance.
The Crusades increased the interest in travel and discovering Europe, which may have lead to the Renaissance. Furthermore, the Crusades serviced an increment in trade and reduced the power of European Nobles, the key to bring about the Age of Exploration.
Explanation: Many historians trace the earliest beginning of the Renaissance to exchanges made during the Crusades. While the Crusades were marked by violence and death, some Europeans traveling through Islamic lands "rediscovered" Greek and Roman learning that Muslim scholars had been studying for centuries.
