Spread of Islam
The spread of Islam spans almost 1,400 years. The early Muslim conquests that occurred following the death of Muhammad in 632 CE led to the creation of the caliphates, expanding over a vast geographical area; conversion to Islam was boosted by Arab Muslim forces expanding over vast territories and building imperial structures over time. Most of the significant expansion occurred during the reign of the rāshidūn caliphs from 632 to 661 CE, which were the first four successors of Muhammad. These early caliphates, coupled with Muslim economics and trading, the Islamic Golden Age, and the age of the Islamic gunpowder empires, resulted in Islam's spread outwards from Mecca towards the Indian, Atlantic, and Pacific Oceans and the creation of the Muslim world. The Islamic conquests, which culminated in the Arab empire being established across three continents, enriched the Muslim world, achieving the economic preconditions for the emergence of this institution owing to the emphasis attached to Islamic teachings. Trade played an important role in the spread of Islam in some parts of the world, such as Indonesia. During the early centuries of Islamic rule, conversions in the Middle East were mainly individual or small-scale. While mass conversions were favored for spreading Islam beyond Muslim lands, policies within Muslim territories typically aimed for individual conversions to weaken non-Muslim communities. However, there were exceptions, like the forced mass conversion of the Samaritans.
Muslim dynasties were soon established, and subsequent empires such as those of the Umayyads, Abbasids, Mamluks, Seljukids, and the Ayyubids were among some of the largest and most powerful in the world. The Ajuran and Adal Sultanates, and the wealthy Mali Empire, in North Africa, the Delhi, Deccan, and Bengal Sultanates, and Mughal and Durrani Empires, and Kingdom of Mysore and Nizam of Hyderabad in the Indian subcontinent, the Ghaznavids, Ghurids, Samanids in Persia, Timurids, and the Ottoman Empire in Anatolia significantly changed the course of history. The people of the Islamic world created numerous sophisticated centers of culture and science, supported by far-reaching mercantile networks, travelers, scientists, hunters, mathematicians, physicians, and philosophers, all contributing to the Islamic Golden Age. The Timurid Renaissance and the Islamic expansion in South and East Asia fostered cosmopolitan and eclectic Muslim cultures in the Indian subcontinent, Malaysia, Indonesia, and China. The Ottoman Empire, which controlled much of the Middle East and North Africa in the early modern period, also did not officially endorse mass conversions, but evidence suggests they occurred, particularly in the Balkans, often to evade the jizya tax. Similarly, Christian sources mention requests for mass conversions to Islam, such as in Cyprus, where Ottoman authorities refused, fearing economic repercussions.
As of 2016, there were 1.7 billion Muslims, with one out of four people in the world being Muslim, making Islam the second-largest religion. Out of children born from 2010 to 2015, 31% were born to Muslims, and currently Islam is the world's fastest-growing major religion.
Terminology
Alongside the terminology of the "spread of Islam", scholarship of the subject has also given rise to the terms "Islamization", "Islamicization", and "Islamification". These terms are used concurrently with the terminology of the "spread of Islam" to refer to the process through which a society shifts towards the religion of Islam and becomes largely Muslim. Societal Islamization has historically occurred over the course of many centuries since the spread of Islam outside of the Arabian Peninsula through the early Muslim conquests, with notable shifts occurring in the Levant, Iran, North Africa, the Horn of Africa, West Africa, Central Asia, South Asia, Southeast Asia, Southeastern Europe, Eastern Europe, and Southern Europe. In contemporary usage, "Islamization" and its variants too can also be used with implied negative connotations to refer to the perceived imposition of an Islamist social and political system on a society with an indigenously different social and political background.The English synonym of "Muslimization", in use since before 1940, conveys a similar meaning as "Islamization". 'Muslimization' has more recently also been used as a term coined to describe the overtly Muslim practices of new converts to the religion who wish to reinforce their newly acquired religious identity.
Rashidun and Umayyad caliphates (610–750)
Within the century of the establishment of Islam upon the Arabian Peninsula and the subsequent rapid expansion during the early Muslim conquests, one of the most significant empires in world history was formed. For the subjects of the empire, formerly of the Byzantine and the Sasanian Empires, not much changed in practice. The objective of the conquests was mostly of a practical nature, as fertile land and water were scarce in the Arabian Peninsula. A real Islamization therefore came about only during the subsequent centuries.Ira M. Lapidus distinguishes between two separate strands of converts of the time: animists and polytheists of tribal societies of the Arabian Peninsula and the Fertile Crescent and the native Christians and Jews existing before the Muslims arrived.
The empire spread from the Atlantic Ocean to the Aral Sea, from the Atlas Mountains to the Hindu Kush. It was bounded mostly by "a combination of natural barriers and well-organized states".
For the polytheistic and pagan societies, apart from the religious and spiritual reasons that individuals may have had, conversion to Islam "represented the response of a tribal, pastoral population to the need for a larger framework for political and economic integration, a more stable state, and a more imaginative and encompassing moral vision to cope with the problems of a tumultuous society." In contrast, for tribal, nomadic, 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: " 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, would 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 caliphs of the Arab dynasty established the empire's first school, which taught the Arabic language and Islamic studies. The caliphs furthermore began the ambitious project of building mosques across the empire, many of which remain today, 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 the Arabian Peninsula had a higher proportion of Muslims among the population.
Abbasid Caliphate (750–1258)
The Abbasids replaced the expanding empire and "tribal politics" of "the tight-knit Arabian elite with cosmopolitan culture and disciplines of Islamic science, philosophy, theology, law and mysticism became more widespread, and the gradual conversions of the empire's populations occurred. Significant conversions also occurred beyond the extent of the empire such as that of the Turkic tribes in Central Asia and peoples living in regions south of the Sahara and north of the Sahel in Africa through contact with Muslim traders active in the area and Sufi orders. In Africa, Islam spread along three routes, across the Sahara and Sahel 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. The initial conversions were of a flexible nature.The reasons that by the end of the 10th century, a large part of the population had converted to Islam are diverse. According to the British-Lebanese historian Albert Hourani, 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. In general, they were not forced to convert, but they suffered from restrictions. They paid a special tax; they were not supposed to wear certain colors; they could not marry Muslim women;."
Most of those laws were elaborations of basic laws concerning non-Muslims in the Quran, which does not give much detail about the right conduct with non-Muslims, but it in principle recognises the religion of "People of the Book" and securing a separate tax from them that replaces the zakat, which is imposed upon Muslim subjects.
Ira Lapidus points towards "interwoven terms of political and economic benefits and of a sophisticated culture and religion" as appealing to the masses. He noted:
"The question of why people convert to Islam has always generated the intense feeling. Earlier generations of European scholars believed that conversions to Islam were made at the point of the sword, and that conquered peoples were given the choice of conversion or death. It is now apparent that conversion by force, while not unknown in Muslim countries, was, in fact, rare. Muslim conquerors ordinarily wished to dominate rather than convert, and most conversions to Islam were voluntary. In most cases, worldly and spiritual motives for conversion blended together. Moreover, conversion to Islam did not necessarily imply a complete turning from an old to a totally new life. While it entailed the acceptance of new religious beliefs and membership in a new religious community, most converts retained a deep attachment to the cultures and communities from which they came."
The result, he points out, can be seen in the diversity of Muslim societies today, with varying manifestations and practices of Islam.
Conversion to Islam also came about as a result of the breakdown of historically-religiously organized societies: with the weakening of many churches, for example, and the favouring of Islam and the migration of substantial Muslim Turkish populations into the areas of Anatolia and the Balkans, the "social and cultural relevance of Islam" were enhanced and a large number of peoples were converted. This worked better in some areas and less in others
During the Abbasid period, economic hardships, social disorder, and pressure from Muslim attackers, led to the mass conversion of Samaritans to Islam.
Along with the religion of Islam, the Arabic language, Arabic numerals and Arab customs spread throughout the empire. A sense of unity grew among many though not all provinces and gradually formed the consciousness of a broadly Arab-Islamic population. What was recognizably an Islamic world had emerged by the end of the 10th century. Throughout the period, as well as in the following centuries, divisions occurred between Persians and Arabs, and Sunnis and Shias, and unrest in provinces empowered local rulers at times.