Christians and Muslims have been in conflict since Muslims established themselves 610 years after the death of Jesus Christ. The conflict came to a head during the events leading to the Crusades and the Crusades themselves. Both sides committed atrocities for the spread of religious beliefs and what each side perceived as the greater good. It is important to remember that Muslim culture conflicts with Christian culture, which is the foundation of American society. How did good turn to evil in the 13th century and how did the different ideologies affect the outcome of the Crusades and how are they currently affecting the Global War on Terrorism? The effects are woven into every fiber of society and we must examine why and how they came to be as well as their continued play in modern society.