Whenever any criticism of Islam's expansion by the sword is mentioned, Muslims point to the Crusades as one of their justifications for their own sordid history. Muslim propagandists were especially vocal concerning the Crusades immediately after the 9/11 attacks. Even ex-President Clinton, in a speech at Georgetown University after 9/11, said that the Crusades were the "root cause" of our present conflict with Muslims. This is the same Mr. Clinton who turned down an offer of the Sudan to deliver Osama 'bin Laden to U.S. jurisdiction previous to 9/11!
Admittedly, in numerous instances, the Crusaders were no better than their cutthroat
counterparts of Islam. Regardless, however, of the bloodbaths attributed to Crusaders by Muslims, the Crusades were belated attempts of Christianity to reclaim principally Christian and Jewish territories over run by Muslims during a period of 400 years. A point: The Dome of the Rock (mosque), in Jerusalem, was built on the ruins of Herod's Temple, and the city of Constantinople, the previous seat of Christianity in Asia Minor, is now called Istanbul.
An important distinction between Crusaders and Muslim warriors is that though the Crusaders certainly had crosses on their armament and clothing, they did not, and could not, justify entry into battle with any words of Christ sanctioning killing, as do Muslims, when they scream "Allah Akbar!" (Allah is greater).
Until Muhammad appeared on the scene, Christianity outside of Europe, extended from beyond the Caspian Sea to the Straits of Gibraltar, and probably numbered around ninety million, mostly in Asia Minor. Asia Minor was the seat of the seven primordial churches, which led to the spread of the Gospel throughout the world. Today, there are less than five million Christians in Asia Minor, and considerably fewer Jews. Perhaps an insolent question, but after numerous generations, and the normal demographic increase expected from the two vibrant societies of Christianity and Judaism, how is it that Christians and Jews make up such an infinitesimal part of Asia Minor’s population, or for that matter, that of the entire world controlled by Muslims? Could it be that, for more than 1,300 years, the choices of conversion to Islam or losing one’s head, fleeing, or being sold into slavery, could have skewed the demographic figures to some extent?
With the superb fighting skills of the Muslims, by the middle of the 7th Century, most of Syria, Persia (Iran), and Egypt had fallen! By about 670 A.D., most of North Africa, Central Asia, and parts of Europe were under the sword of Islam. The Muslims crossed the Pyrenees and were close to conquering all of Europe until their defeat at Tours (France) by Charles Martel, in 732, exactly a century after the death of Muhammad. This defeat saved Western Civilization, as did two separate Muslim defeats at the gates of Vienna, some 150 years apart. One of the Muslim defeats at Vienna occurred on September 11, 1683. Osama 'bin Laden took this date for his attack of 9/11/01. Unfortunately, on the way to Vienna, most of the Balkans was placed under the yoke of Islam. This tragedy remains with us today.
Perhaps the most important distinction, between the atrocities attributed to the Crusaders and those of Islam, is the following: The Crusaders, at their worst, were violating all principles of Christianity. But the Muslims, when they murdered, raped, pillaged, and enslaved, were only following the personal example set by the founder of Islam, their revered prophet Muhammad, and his (Allah’s / Muhammad's ) exhortations of the Koran!
There were several Crusades, over almost exactly 200 years, commencing in 1095, the last of the eleventh century, and lasting until the end of the thirteenth century, when the last of the Crusaders were annihilated in Palestine and Syria.