Correct me if I’m wrong. In the first crusade there were no Muslims. They were pagans. It was Mohamed who noticed that the Christians, unified by their religion, could fight side by side even though some did not have a common language, who started Islam. Islam was intended to be 180 degree counter to Christianity. It unified the pagans and granted its new members special privileges in loot and slaves that were not enjoyed by non-members.
Where Christianity held wider aspirations Islam’s only purpose, originally, was to destroy Christianity. Where Christianity was one component of a wider society, Islam was intended to supplant all components and become law, government, education and creed all in one.
In the first crusade there were no Muslims.
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Historical source (based on good primary sources)?