Make no mistake: this book is no apology-manual for the history of the Jews in Islam. Like always, Bernard Lewis presents the facts as he finds them and does not appear to have an agenda beyond that. He does not make the typical straw man argument that many other authors of recent times have made about Islam, that it is anti-semitic, violent, and bigoted, whereas Christianity is a religion of peace because Jesus preached passive resistance and the gospels have many peaceful quotations. To the contrary, he actually claims that ant-semitism never existed in Islam until it was introduced by Christian European colonialists during the 18th century upward.
Lewis defines anti-semitism as: A. The obsessive fanaticism of and about Jews. B. The assigning of Jews of cosmic evil and blaming all of the world's ills on them and C. Holding Jews to double-standards. According to him, persecuting the Jews and disliking them is not anti-semitism, it is a normal (and unfortunate) part of the human condition to dislike and persecute those who are different from us. That being stated, anti-semitism never existed in Islam up until recent times. However, persecution and hatred of the Jews did.
The "dhimmi" laws of Islam are well-known by many at the present time. However, Lewis describes how the dhimmi laws were applied at different times and across different Muslim societies. The Ottoman Turks were by far the best in their treatment towards the Jews. Jews were generally unmolested in their religious activities and had several opportunities to reach high social positions and prestigious professions. The Turks never saw the Jews as dangerous, and often saw the Jews as useful, because of their ties to Europe and their knowledge of European inventions and artillery. However, most Jews were poor and there were a few notable incidents of violent fanaticism that occurred occasionally in Turkey.
The Arabs were "moderate" in their treatment of the Jews. At times they were hostile, viewed themselves as innately superior and often dismissed or debased the Jews. However, under Islamic Spain, Jews were able to reach high positions, notably the famous Rambam. The Persians, on the other hand, were by far the worst in their treatment of the Jews. The Persians treated Jews as an "untouchable" social class, which obviously pre-dates Islam and comes from their caste-oriented neighbor India. The Persians had a plethora of humiliating laws and decrees, such as that Jews could not walk outside when it was raining, because their dirtiness would rub off of them and drip onto the street, thus dirtying the shoes of Muslims. This really sheds led onto the modern quagmire of Iranian-Israeli relations and hostility.
I would also like to add my own insights: One must remember that Islam was never a sect within Judaism, that Mohammed and his early followers were not Jews and that Muslim theology does not believe the Jews were chosen. Christianity, on the other hand, was a sect within Judaism, Jesus and his early followers were all Jews and that Christian theology still believes that the Jews were chosen. There is an inherent anti-semitism within Christianity because of these three points. This however, does not exist in Islam. Islam views Jews (and Christians) as being a flawed version of the one true faith, that are tolerated as natural inferiors, dhimmis. The fanatical obsession with Jews and the assigning them with cosmic evil with introduced to Islam by Christian imperialist interlopers. The Jews became a convenient scapegoat for the miserable condition that most Muslims and that time and still to these times are living in. That last thesis is developed in more detail in some of Lewis' other works, such as "Middle East Mosaic", "The Arabs in History" and some of his videos on Youtube. Lewis ends the book with then end of what he calls the "Judeo-Islamic tradition". Because of the relatively recent introduction of anti-Semitism into the Middle East from Europe, the tradition has come to an abrupt end.