Bernard Lewis on the thousand-year Muslim threat that kept Europe under constant siege: “We tend nowadays to forget that for approximately a thousand years, from the advent of Islam in the 7th century until the second siege of Vienna in 1683, Christian Europe was under constant threat from Islam. The double threat of conquest and conversion, of military invasion and religious subversion, hung over Europe. All but the easternmost provinces of the Islamic realm had been taken from Christian rulers… North Africa, Egypt, Syria, even Persian-ruled Iraq, had been Christian countries, in which Christianity was older and more deeply rooted than in most of Europe. Their loss was sorely felt and heightened the fear that a similar fate was in store for Europe.”