Answer:
Millions of lives were lost due to the Crusades; However, many new advancements were spread because of the Crusades.
- The Europeans learned about new concepts in math as well as a new numbering system, called Hindu Arabic Numerals, which we still use today.
- They gained access to new medical knowledge and a variety of other ideas.
- The Crusades also opened up many new trade possibilities with goods that Europeans never had access to before them.