In the beginning, they were a group of knights in simple clothes, on thin horses, coming out of the Arabian Peninsula with weapons, of which the sword was the most important, a strong faith, and a rare toughness. Even though their numbers weren't large, within a century they had defeated the two superpowers of their age (the Sassanid and Byzantine empires) and the political presence of the Muslim state became a major factor in the world of the eighth century AD. Never before had such vast areas been conquered in such a short period, nor have the results of such conquests lasted to the present, as those of the Islamic conquests have. This remarkable historical phenomenon has led many historians and scholars to ask questions throughout the ages. This book focuses on the position of eastern Christians, in general, from the Islamic conquest's movement, and how they dealt with the religion of Islam and with Muslims. In this context, the author endeavored to include complete (or almost complete) original texts in an attempt to recreate the image that the writers of the age had. In addition, he examines the historical development of the image of the other in Europe and the Islamic World. There is a multifaceted relationship between the Islamic world and Europe, which changed over the centuries according to the circumstances that left their markings on the image of the "other" on both sides. The author highlights the difference between the concept of "tolerance" in the Western culture in general, and in the Arab-Islamic culture in the past and present, showing how this difference has had a clear impact on the image of the other in both cultures, and how it still controls the position of each side.