aye, the 14th century was a typo, I was typing too fast to notice it. although, Cyprus was converted from its former Byzantine heritage to a Crusader state that remained under Christian rule until 1571, but I wouldn't really count that. anyway, when the power in the Outremer states began shifting from the Kings to the military orders (Templars and Hospitallers) the end was pretty much near. with the fall of Aleppo, the only noteworthy Outremer cities still under Christian control were Montfort (held by the Teutonic Knights), Belvoir (held by the Hospitaller Knights), Chastel Blanc, and Saphet (both held by the Templar Knights). When the Pope called for a crusade against Aragon in 1282, that, along with the shift of power from the royalty to the military orders, ensured the end of the Outremer states. I believe that Acre, the last of the major Christian states, fell in 1290 to a combined effort of multiple Muslim nations and tribes. the last permanent Christian presence, a Templar garrison on the island of Ruad, lasted until 1302.
I don't know where you got your information about this agreement, but
www.clownpenis.fart is not the most historically accurate source. most of the crusader states were under CONSTANT attack, whether it be just a raid or a full out siege. in the north, it was mostly the Seljuk Turks and in the south, the Kaliphates were the most serious threat (at least until the Mamluks began gaining influence in Egypt, but that wasn't until much later). Like I said, there was indeed some brutality on the part of the Christians, but the muslims were by far the MOST violent during the Crusades. know why? because they were a warrior society taught to show no mercy to the enemies of their home and the enemies of Islam. of course, this period of history is marked by violence, so to say that neither side was so would be foolish.
that "crusade" against the Byzantines was doomed from the start and Alexius IV was a moron. of course, there were times when the Byzantine walls were manned ENTIRELY by Italian mercs, so maybe it wasn't so hopeless. the decadent Byzantine Empire was simply on its last leg. i think that we are in agreement on this point.
as for Vince's claim, I don't think that the Muslims could have taken over the world. hell, if it was the entire Empire of Islam against the forces of the Holy Roman Emperor, I think the Muslims would be hard-pressed to win. now imagine them trying to tackle the Chinese. the mongols created some problems for the world and would have created more after their...acceptance (not conversion) of Islam had they desired to. although the Hungarians and Polocks had severly damaged their forces at Wahlstadt and Mohi, the Mongols were adept at winning while outmanned. it was never their intent to conquer Europe, however, they only wanted to remove the threat of Duke Henry of Silesia and King Bela of Poland while reclaiming the Cumans who had fled to Hungary. so no, I don't think that there was ever any danger of a Muslim conquest of the world.