“The religious decay in Arabia shortly before Islam may well be taken in a negative sense, in the sense of the tribes losing the feeling of kinship with the tribal gods. We may express this more concretely by saying that the gods had become gradually more and more nebulous through the destructive influence exercised, for about two hundred years, by Jewish and Christian ideas, upon Arabian heathenism “—_H. Hirschfeld_, in the “Journal of the Royal Asiatic Society.” In order to understand the genesis of Islam we must know something of the condition of Arabia before the advent of Mohammed. We shall then be able to discover the factors that influenced the hero-prophet and made it possible for him so powerfully to sway the destinies of his own generation and those that were to follow. Mohammedan writers call the centuries before the birth of their Prophet _wakt-el-jahiliyeh_—“the time of ignorance”—since the Arabs were then ignorant of the true religion. These writers naturally chose to paint the picture of heathen Arabia as dark as possible, in order that the “Light of God,” as the prophet is called, might appear more bright in contrast. Following these authorities Sale and others have left an altogether wrong impression of the state of Arabia when Mohammed first appeared. The commonly accepted idea that he preached entirely new truth and uplifted the Arabs to a higher plane of civilization is only half true.[49] No part of Arabia has ever reached the high stage of civilization under the rule of Islam which Yemen enjoyed under its Christian or even its Jewish dynasties of the Himyarites. Early Christianity in Arabia, with all its weakness, had been a power for good. The Jews had penetrated to nearly every portion of the peninsula long before Mohammed came on the scene.[50] In the “Time of Ignorance” the Arabs throughout the peninsula were divided into numerous local tribes or clans which were bound together by no political organization but only by a traditional sentiment of unity which they believed, or feigned to believe, a unity of blood. Each group was a unit and opposed to all the other clans. Some were pastoral and some nomadic; others like those at Mecca and Taif were traders. For many centuries Yemen had been enriched by the incense-trade and by its position as the emporium of Eastern commerce. Sprenger in his ancient geography of the peninsula says that: “The history of the earliest commerce is the history of incense and the land of incense was Arabia.” The immense caravan trade which brought all the wealth of Ormuz and Ind to the West, must have been a means of civilization to the desert. The tanks of Marib spread fertility around and the region north of Sana was intersected by busy caravan-routes. W. Robertson Smith goes so far as to say that “In this period the name of Arab was associated to Western writers with ideas of effeminate indolence and peaceful opulence ... the golden age of Yemen.”