Their history was as much one of accommodation than confrontation.
As for religious hostility - at the time of the first crusade, it is estimated that over 50% of the population of Syrian and Palestine was Christian - after 500 years of Muslim rule.  It was after the 3rd Crusade, I believe, that the Muslims finally started to think of Christians as a 5th column - and begin to make proselytization and conversion state policy.