I think because they didn't really like jewish people they started racism so they were part of racism and that is why they were many of them killed because of their skin color and how they looked.
The Holy Land are found in the spread of a warrior Asiatic tribe. In 1071, the Seljuk Turks defeated the Byzantine army at the Battle of Manzikert, thereby occupying all of Asia Minor, including Palestine. As stories of atrocities committed against Christian pilgrims filtered back to Europe, the Byzantine Emperor Alexius Comnenus appealed for help against the Seljuks. Pope Urban II called for a crusade against the Muslims in 1095. The stated goal of this crusade was to recapture the Holy Land and ensure safety for Christian pilgrims visiting sacred sites. However, many of the crusaders saw it as the perfect opportunity to serve God and simultaneously make a fortune in looting and ransom.
