Allow me to remind you that I refuse to capitalize names and words that I don't respect.
The Gates of Vienna refers to the battle, in 1683, when Jan Sobieski, the king of Poland, joined forces with Leopold, the Emperor of the Holy Roman Empire, and defeated the Turkish Ottoman Empire, muslims seeking to rule the whole of Europe. For quite a few reasons, some of which can be read here , the Ottoman Empire had been successful at taken large bites out of the Holy Roman Empire and also of those parts of Europe which were separate.
While much of Europe was playing the game that modern-day Europe - and to a lesser extent, our government here in America - is playing, one of appeasement, of begging for a negotiated peace from the muslims, each country hoping to be the last to be "eaten" (by riots, terrorism, and demographic jihad today as opposed to the open warfare they faced back then), Jan Sobieski was bright enough to understand that appeasement simply cannot work with an ideology that demands your slavery or your death - or both.
So he allied his army with that of Leopold, along with a relatively small number of troops from Vienna itself, and this amalgamation defeated the muslims, stopping them - at the gates of Vienna. Leopold is given credit for the defeat of the Ottoman army, but it is extremely unlikely he would have fought and won, had not Sobieski brought both his troops and his willingness to enter the fray.
The authors of the blog site, The Gates of Vienna, work hard to keep us all informed of what is happening in the European clash with islam. They know that, should Europe fall, as it appears it might, it will make it incredibly more difficult for America to avoid succumbing to the forces of islam, too. America is already severely handicapped by strong Progressive forces (aided and abetted by the Democratic Party) and a President who not only favors muslims over America, islam over any other culture, but who also is extremely desirous of seeing America humbled before islam and the rest of the world.
The threat is real. As it is such a successful weapon in the Progressives' arsenal, the Left pretends the threat offered by islam is simply "conspiracy theory". Any thought or opinion they wish to discredit, they name a "conspiracy", first. To paraphrase a quote, "Those whom the Left would destroy, they first call mad."
As I have written many times already, a study of the qu'ran, the "holy" book of the muslims, of islam, tells the world very plainly what their intentions are: a Universal Caliphate where everyone is either a muslim, a slave, or dead. There is no "radical" islam, there are no "radical" muslims. There are only true, orthodox muslims, who follow the commands, the dictates of the qu'ran, the directions of the hadith. There is only islam, where there is no law, no government but sharia. Where there is no G-d but allah, and mohammed (piss be unto him) is his prophet. islam is there for everyone to see, quite plainly and honestly, right out in the open - you have only to look to ISIS/ISIL and you see islam demonstrated "in all its gory" (not glory) truth. ISIS is the distillation of the pure and true islam, as commanded by mohammed, the pedophile, the raper of nine-year-old little girls, who made up a fake religion to attract arab men into an army which was promised female slaves to rape, abuse, and sell ("war brides"), and little girls to "marry" - and then rape, abuse, and keep as chattel, as slaves to their lusts and pride.
Please do read the posts at The Gates of Vienna. In spite of what the Left will tell you, shrilly and with a full complement of lies and deception, what is posted at GOV is the frightening truth.