This covers a broad - very broad - historical spectrum, in fact 2,000 years, from the rise of Christianity to the present, crucial period.
At the beginning of the Christian era, most of what we now call the Middle East was divided between the regions ruled by the Roman Empire and those dominated by its great rival for centuries, the Persian/Parthian Empire, or Iran. When Rome itself fell, its Eastern (Byzantine) Empire remained as a major power, until the rise of Islam which not only challenged (and ultimately destroyed) it, but swept over North Africa and across into Spain and Southern France, Sicily and even Italy. In fact, to a large extent this book is virtually a history of Islam, from its raw beginnings among primitive Arab tribesmen through the Baghdad Caliphate and other regimes to its apotheosis in the Ottoman Empire, one of the greatest powers the world had ever known. The Crusades, seemingly, made relatively little impression on the East - certainly their impact was small compared to that of the Mongols, though Bernard Lewis thinks Mongol destruction has been exaggerated. Islam built upon the legacy of ancient cultures, of Greek science (particularly mathematics), and on its own fervent drive and moral conviction - which allowed considerable room for booty and plunder although conversion was rarely compulsory.
There is little reasonable doubt that for much of the Middle Ages, the East was culturally more advanced than Europe, but later it fell behind, and the terminal decline of the Turkish Empire, in particular, affected the whole international power structure and was a factor leading to the first World War. The final chapters trace the gradual emergence from Western domination and colonialism and Bernard Lewis thinks - that while the "outside powers" will still act to defend their own interests (markets and oil), "otherwise the peoples and governments of the Middle East, for the first time in two centuries, will determine their own fate". In view of the current situation, his book makes doubly valuable reading.