In contrast, for sedentary and often already monotheistic societies, Islam was substituted for a Byzantine or Sassanian political identity and for a Christian, Jewish or Zoroastrian religious affiliation. Conversion initially was neither required nor necessarily wished for, The Arab conquerors did not require the conversion as much as the subordination of non-Muslim peoples. At the outset, they were hostile to conversions because new Muslims diluted the economic and status advantages of the Arabs.
Only in subsequent centuries, with the development of the religious doctrine of Islam and with that the understanding of the Muslim, “ummah”, did mass conversion take place. The new understanding by the religious and political leadership in many cases led to a weakening or breakdown of the social and religious structures of parallel religious communities such as Christians and Jews.
The calipha of the Umayyad dynasty established the first schools inside the empire, called “madrasas”, which taught the Arabic language and Islamic studies. They furthermore began the ambitious project of building mosques across the empire, many of which remain today as the most magnificent mosques in the Islamic world, such as the Umayyad Mosque in Damascus.
At the end of the Umayyad period, less than 10% of the people in Iran, Iraq, Syria, Egypt, Tunisia and Spain were Muslim. Only on the Arabian peninsula was the proportion of Muslims among the population higher than this.
The time of the Abbasid Dynasty (750-1258) is the second great dynasty with the rulers carrying the title of 'Caliph'.
Expansion ceased and the central disciplines of Islamic philosophy, theology, law and mysticism became more widespread and the gradual conversions of the populations within the empire occurred. Significant conversions also occurred beyond the extents of the empire such as that of the Turkic tribes in Central Asia and peoples living in regions south of the Sahara in Africa through contact with Muslim traders active in the area and sufi missionaries.
In Africa it spread along three routes, across the Sahara via trading towns such as Timbuktu, up the Nile Valley through the Sudan up to Uganda and across the Red Sea and down East Africa through settlements such as Mombasa and Zanzibar. These initial conversions were of a flexible nature and only later were the societies forcibly purged of their traditional influences.
The reasons why, by the end of the 10th century CE, a large part of the population had converted to Islam are diverse. One of the reasons may be that Islam had become more clearly defined, and the line between Muslims and non-Muslims more sharply drawn. Muslims now lived within an elaborated system of ritual, doctrine and law clearly different from those of non-Muslims.
The status of Christians, Jews and Zoroastrians was more precisely defined, and in some ways it was inferior. They were regarded as the 'People of the Book', those who possessed a revealed scripture, or 'People of the Covenant', with whom compacts of protection had been made.
Source: Wikipedia English, 20 February 2011