'I remember very clearly," Prof. Yom-Tov Assis, head of the Ben-Zvi Institute for the Study of Jewish Communities in the East, says of his youth in Aleppo, "how a Syrian officer entered our home with his gun and brought a Palestinian refugee, accusing my parents of being responsible for her terrible condition and demanding that we give her money and clothing. "I remember the attempts to break through the gates to our building, all the occupants of which were Jewish. I remember how the people used to shout in the streets, 'Palestine is ours; Jews are dogs!' Demonstrations took place daily, from the time the United Nations decided to divide Palestine into Jewish and Arab parts. Clubs and synagogues were burned. Jews were attacked." In 1949, the Assis family fled the antagonism of Syria for the tranquility of Lebanon. "We used to spend our summer holidays in the Lebanese mountains... It was paradise," he fondly recalls. When they left, "we pretended that we were going on our usual summer holiday... but we never went back." Like the nearly 900,000 Jews who left - or were forced from - Muslim countries shortly after Israel's independence, Assis says, his family "left behind property, left behind wealth. We left behind everything." From Lebanon, Assis moved to Turkey, and then to London, before making aliya in 1971. Ever since, the medieval scholar has had to disabuse people of what he calls "the fallacy of Jewish happiness under Muslim rule." That's the assumption that the "Golden Age" in Andalus (Muslim Iberia and North Africa), from the mid-700s to the mid-1100s, was both idyllic and common to Islamic rule in other times and places. Not only is that not the case - although Jews were generally better off under Muslim rule through the 10th century, there were large-scale pogroms in the 11th century - but, as Assis points out, it also disregards the fallout from the invasion of the Almohads, who "destroyed Jewish life" in the latter part of the 12th century. "They left no Jewish community intact. There were many who were killed, many who were forcibly converted to Islam, many who had to escape - including the family of Maimonides, and other famous families," Assis says. "So to suggest that there was no persecution of Jews under Muslim rule is absurd." Here's another disconcerting thought: One of the main causes of the relative tolerance that Jews experienced - a deep respect for the scientific and cultural contributions of others - has since been so absent from Islamic life that, in the past 1,000 years, the number of books translated into Arabic is less than the number of books translated in Spain in just one year. Or, as Assis puts it, "Today, the literary and scientific production of the entire Muslim world in the course of one year is but a fraction of the output of tiny Israel." In such an environment, he adds, "the Golden Age cannot be repeated. There's no way that one could even think of it." Given this reality, how has the myth of Muslim tolerance become so widely accepted? "Jewish historiography is largely to blame," Assis says. "For a long time, it was very Europe-centric. Those who wished to emphasize the difficulty of Jewish life in Christian Europe (such as 19th-century Jewish historian Heinrich Graetz), pointed to the Jews' Golden Age in Spain as the standard of treatment under Muslim rule. But they never gave any other examples." That, he says, is because there are none to give. "Yes," Assis concedes, "persecution of Jews was, in general, less cruel and less frequent in Muslim lands than it was in Christian Europe. Of course, there was nothing that could compare to the Holocaust. But there were numerous cases of Jews being treated terribly - in Morocco, in Yemen, in Iran, in Iraq... indeed, practically everywhere." In short, Assis concludes, there is ample evidence that Muslim anti-Semitism is not merely a reaction to Jewish settlement in Palestine. "And even if it were," he says, "so what? The Jews of Morocco, Egypt, Iraq" - and Aleppo, Syria, of course - "what did they do?"