Answer:
1. The crusades were a series of religious wars fought between Christians and Muslims in the 11th, 12th, and 13th centuries. The first Crusade was launched by Christians in an attempt to reclaim the Holy Land (Jerusalem and the surrounding areas) from Muslim control.
2. The crusades were launched by the Christians, and Muslims were the ones defending their territories and holy places.
It's worth noting that the term "crusade" is a Western term, and is not the term used by Muslims to describe these conflicts. The Muslim equivalent of the term "crusade" is "jihad", which refers to the struggle to maintain and spread the Islamic faith.