Because this is true, a brief refresher of the Siege of Vienna is in order, particularly as its anniversary is right around now:

“Austria acts against Muslims almost every day because of their subconscious fear of Turks,” writes Turkish historian Erhan Afyoncu in the Daily Sabah . “Austrians have not forgotten the fear and their emperor’s escape in the Battle of Vienna in 1683. When Turks were defeated in the Battle of Vienna, Europeans were so happy…”

Around July 15, 1683, the largest Islamic army ever to invade European territory -- which is saying much considering that countless invasions preceded it since the eighth century -- came and surrounded Vienna, then the heart of the Holy Roman Empire and longtime nemesis of Islam.

Some 200,000 Muslim combatants, under the leadership of the Ottomans -- the one state in nearly fourteen centuries of Islamic history most dedicated to and founded on the principles of jihad -- invaded under the same rationale that so-called “radical” groups, such as the Islamic State, cite to justify their jihad on “infidels.” Or, to quote the leader of the Muslim expedition, Grand Vizier Kara Mustafa, because Vienna was perceived as the head of the infidel snake, it needed to be laid low so that “all the Christians would obey the Ottomans.”

This was no idle boast; sources describe this Mustafa as “fanatically anti-Christian.” After capturing a Polish town in 1674 he ordered all the Christian prisoners to be skinned alive and their stuffed hides sent as trophies to Ottoman Sultan Muhammad IV. Such supremacist hate was standard and on display during the elaborate pre-jihad ceremony presaging the siege of Vienna. Then, the sultan, “desiring him [Mustafa] to fight generously for the Mahometan faith,” to quote a contemporary European source, placed “the standard of the Prophet… into his hands for the extirpation of infidels, and the increase of Muslemen.”

Once the massive Muslim army reached and surrounded the walls of Vienna around July 15, Mustafa followed protocol. In 628, his prophet Muhammad had sent an ultimatum to Emperor Heraclius: aslam taslam, “submit [to Islam] and have peace.” Heraclius rejected the summons, jihad was declared against Christendom (as enshrined in Koran 9:29), and in a few decades, two-thirds of the then Christian world -- including Spain, all of North Africa, Egypt, and Greater Syria -- were conquered.

Now, over a thousand years later, the same ultimatum of submission to Islam or death had reached the heart of Europe. Although the Viennese commander did not bother to respond to the summons, graffiti inside the city -- including “Muhammad, you dog, go home!” -- seems to capture its mood.

So it would be war. On the next day, Mustafa unleashed all hell against the city’s walls; and for two months, the holed-up and vastly outnumbered Viennese suffered plague, dysentery, starvation, and many casualties -- including women and children -- in the name of jihad.

Then, on September 12, when the city had reached its final extremity, and the Muslims were about to burst through, Vienna’s prayers were answered. As an anonymous Englishman explained:

After a siege of sixty days, accompanied with a thousand difficulties, sicknesses, want of provisions, and great effusion of blood, after a million of cannon and musquet shot, bombs, granadoes, and all sorts of fireworks, which has changed the face of the fairest and most flourishing city in the world, disfigured and ruined [it]... heaven favorably heard the prayers and tears of a cast down and mournful people.

The formidable king of Poland, John Sobieski, had finally come at the head of 65,000 heavily-armored Poles, Austrians, and Germans -- all hot to avenge the beleaguered city. Arguing that “It is not a city alone that we have to save, but the whole of Christianity, of which the city of Vienna is the bulwark,” Sobieski led a thunderous cavalry charge -- history’s largest -- against and totally routed the Muslim besiegers.

Although a spectacular victory, the aftermath was gory: before fleeing, the Muslims ritually slaughtered some 30,000 Christian captives collected during their march to Vienna -- raping the women beforehand. On entering the relieved city, the liberators encountered piles of corpses, sewage, and rubble everywhere.

It is this history of Islamic aggression -- beginning in the fourteenth century when Muslims first established a foothold in Eastern Europe (Thrace), and into the twentieth century when the Ottoman sultanate finally collapsed -- that informs Eastern European views on Islam. As one Pole, echoing the words of Sobieski, said, “A religious war between Christianity and Islam is once again underway in Europe, just like in the past.”

Whereas Western nations cite lack of integration, economic disparities, and grievances to explain away the exponential growth of terrorism, violence, and rapes that come with living alongside large Muslim populations, Eastern nations tend to see only a continuity of hostility.

Note: The above account is excerpted from Sword and Scimitar: Fourteen Centuries of War between Islam and the West -- a book that CAIR and its Islamist allies did everything they could to prevent the U.S. Army War College from learning about.