The Crusades & Islamic Expansion
|Siege of Acre|
At a Georgetown University speech, President Bill Clinton claimed the crusaders entered Jerusalem with "blood running up to their knees," and claimed Muslim rage against the West is inspired by our crusading ancestors: "Those of us who come from various European lineages are not blameless."  In other words, it’s white people's fault.
Historian Sir Steven Runcimen wrote a three volume history on the Crusades before dismissing them as "nothing more than a long act of intolerance in the name of God." 
The anti-crusade movement began with eighteenth century historian Edward Gibbon. Gibbon hated Christianity and described the onset of the Middle Ages as "the rise of barbarism and religion." Gibbon said: "The principle of the crusades was a savage fanaticism," and claimed it was motivated by greed. 
Even the briefest research quickly exposes the ignorance of these opinions. The Crusades were a defensive action against Islamic conquest and oppression.
Far from offensive, the Crusades preserved the Byzantine Empire and helped save Christendom from advancing Muslim hordes.
ISLAM'S VIOLENT ROOTS
The prophet Mohammad told his followers to: "Fight those who believe not in Allah nor the Last Day… nor acknowledge the religion of Truth… until they pay the Jizya with willing submission, and feel themselves subdued." (Quran, 9:29)
Mohammad practiced what he preached. Before his death in AD 632 he conquered the entire Arabian Peninsula using ruthless tribal warfare.
His Muslim disciples wasted no time following his example. In the twenty years following their leader's death they conquered Damascus, Jerusalem, Alexandria, and invaded Sicily and Egypt in the name of Allah. Most of this territory was formally Christians.
In the twenty years following they conquered the Cyzicus peninsula, Cyprus, Rhodes, and laid siege to Constantinople.
By AD 718 Islamic armies had brutally subjugated the entirety of North Africa and had marched into Europe wrestling away most of the Iberian peninsula from Christian Visigothic kingdoms. Three years later, they invaded Gaul before being crushed by the Franks at the Battle of Tours (AD 732).
Islam continued its expansion by violence for the next three centuries. Mohammad's followers inflicted numerous horrors on Christian and European populations. By 1090 seventy percent of the Christian world had been wiped away by Muslim conquest. The birthplace of the Christian religion, Jerusalem, was occupied by invaders.
Figures indicate that during its early wars the "religion of peace" caused the deaths of 60,000,000 Christians, 10,000,000 Buddhists, and over 80,000,000 Hindus. Altogether, the Islamic conquests were twenty-five times more deadly than the Nazi Holocaust. 
The Muslims did not treat their Christian subjects well. Atrocities were common.
In AD 705, Arab viceroy Muhammad ibn Marwan destroyed the Armenian nobility. He locked them in churches and burned the buildings down. Marwan also crucified several of them. Hundreds of people were killed in the massacres.
In AD 796, twenty monks from the Mar Saba monastery were burned to death by Muslims. In 1022 Gerald of Thouars, an abbot pilgrim on his way to the holy land, was imprisoned and murdered by Islamists.
In 1048, the Muslims attacked the city of Ardzen. The city agreed to surrender peacefully, but the invaders slaughtered 140,000 people after entering the gates.
In 1063, a Muslim army attacked the city of Ani and slaughtered its inhabitants, according to an eyewitness, “the dead bodies were so many that they blocked up the street.”
In 1064, Christian pilgrims led by Bishop Gunther of Bamberg were ambushed by Muslims as they traveled to Jerusalem. Most were murdered.
In the eleventh century, 30,000 churches were burned and pillaged during the reign of El-Hakim.
CHRISTIANS DEFEND THEMSELVES
By the late eleventh century the Byzantine Empire was the only barrier between violent Muslim expansionism and Euroethnic Christians. Europe realized it needed to check Muslim barbarism if it hoped to survive.
The Crusades were a delayed defensive action. Their need arose after the disastrous Battle of Manzikert (1071) in which the Muslims took over most of the Anatolian peninsula. After the battle, the defeated Byzantines asked the Western Church to organize European troops to save Christianity.
While preaching the First Crusade, Pope Urban II delivered an inspiring speech:
"From the confines of Jerusalem and the city of Constantinople a horrible tale has gone forth and very frequently has been brought to our ears, namely, that a race from the kingdom of the Persians [Muslims], an accursed race, a race utterly alienated from God, a generation forsooth which has not directed its heart and has not entrusted its spirit to God, has invaded the lands of those Christians and has depopulated them by the sword, pillage and fire; it has led away a part of the captives into its own country, and a part it has destroyed by cruel tortures; it has either entirely destroyed the churches of God or appropriated them for the rites of its own religion…
Let the deeds of your ancestors move you and incite your minds to manly achievements; the glory and greatness of king Charles the Great, and of his son Louis, and of your other kings, who have destroyed the kingdoms of the pagans, and have extended in these lands the territory of the holy church. Let the holy sepulcher of the Lord our Savior, which is possessed by unclean nations, especially incite you, and the holy places which are now treated with ignominy and irreverently polluted with their filthiness. Oh, most valiant soldiers and descendants of invincible ancestors, be not degenerate, but recall the valor of your progenitors." The First Crusade ended in victory, and resulted in the the establishment of the Kingdom of Jerusalem. Although the crusaders never recovered all the lands conquered by Muslim hordes, their brief victory might have saved Christian Europe.
 Thomas F. Madden. "Rivers of Blood: An Analysis of One Aspect of the Crusader's Conquest of Jerusalem." Revista Chilena de Estudios Medievales. Pg. 26.
 Steven Runciman. "A History of the Crusades, Vol. III: The Kingdom of Acre and the Later crusades." Pg. 480.
 Edward Gibbon. "The Decline and Fall of the Roman Empire" (1917). Pg. 1086.
 Dr. William Warner. "The Study of Political Islam." Frontpagemag.com.
 Charles William Colby. "Selections from the Sources of English History." Pg. 48.