The Islamic conquests of areas outside Arabia began in the seventh century. In the first wave of conquest, the Arabs took Syria, Egypt, and the Sasanid Empire. In the late seventh and early eighth centuries, Islamic forces took Tunisia, Spain, Algeria, Morocco, and Sind. Common explanations for the rapidity of the Muslim advance include lust for treasures and valuables, religious devotion, and the weakness of the foes of Islam. The most convincing explanation finds the causes of Muslim expansion in the talent of the Muslim leaders and the structure of Arab society. During the period of expansion the Arab forces were organized into regular, paid armies and kept in military camps and garrison towns so that they did not overrun the countryside. The Arab Muslims became minority rulers, thinly spread over non-Muslim societies that they dominated and taxed, but did not try to convert.
2. What were the causes of the decline of the caliphate?
Abbasid power began to decline in the second half of the ninth century as the caliphs found it impossible to maintain control over their vast territory. One factor in the decline of Abbasid power was the difficulty of transportation and communications. Another factor was the dissatisfaction of the non-Muslim provincial populations with a political and economic system that was centered on Baghdad. The reasons that Abbassid territory diminished between 750 to 850 CE, fracturing into the Umayyads (Spain), Idrissids (Morocco), Aghlabids (Algeria, Tunisia, Sicily), and other smaller states consisted of religious issues, such as those between the Abbassids and the Shi'ites, distance, no effective trade routes, and political issues.
3. Read the description of the developments in Zoroastrianism and in Christianity on pages 232–233 and then the descriptions