That would be a Crusade. The first crusade occurred in 1095 or so and there were crusades over the next 200 years.
Well, the Christians in europe believed that palestine was the Holy Lands* and wanted to regain them from the Muslims. *Holy Lands=Place where Jesus supposedly lived, died, and preached.
The Holy Lands are important to both the Christians and Muslims. The crusades began when the Muslims began denying Christians access to the sacred sites.
One major goal of the Christian church during the Crusades was to reclaim and secure holy sites in Jerusalem and the Holy Land from Muslim control, as they were considered sacred to Christians. The church saw the Crusades as a way to protect Christian pilgrims and expand Christian influence in the region.
The Christians wanted the Holy Lands.
The Holy Bible is the sacred text for Christians.
Win control of the Holy Lands, the background to the Bible, and in particular the Holy City, Jerusalem itself. Medieval Christians saw it as a great sin to have such sacred places held by "heathens".
The Crusades were about re-capturing the Holy Land, which is the sacred land for Christians.
The Holy Bible is from God. God love Christians and Christians love God.
The same sight that is also sacred (Holy) for the Jews and the Christians., especialy Masjid i Umar.
Crusades occurred mostly to regain the Holy Lands - The Kingdom of Jerusalem from the muslims.
The first crusade started because the Christians wanted to regain the holy land of Jerusalem from the Muslims.
Holy Land.