Islam was not the first foreign religion to arrive in Central Asia. In fact, the region had already been exposed to many foreign systems of belief prior to the coming of Islam in the seventh century. Local merchants conducting long-distance trade along the Silk Road came into contact with many different religious doctrines; the trade route served as a conveyor of not only goods but also concepts. Generally, intellectual diffusion is not a one-way street, as western ideas traveled eastward and eastern concepts filtered into the west. In this manner, the Silk Road carried Buddhism, Judaism, Zoroastrianism (an Iranian religion with both monotheistic and dualist elements), Siberian Shamanism, and even Nestorian Christianity to Central Asia. The great number of religions found in the area at the introduction of Islam testified to the great tolerance of the region. By the tenth century, however, all of the non-monotheistic faiths had disappeared from Central Asia in the aftermath of Islamic conquest.
It was Qutayba ibn Muslim (669 – 716) who expanded the presence of Islam in Central Asia during the eighth century, as the general’s forces swept into the area, defeated the Persians, and by 715 CE completed their conquest of Transoxiana, the region located beyond the Oxus River. A decisive Arab Muslim victory over the Chinese at the Battle of Talas River in 751 secured Central Asia and repulsed the only major challenge to Islamic rule. The triumph over the Chinese made it possible for Islam to become entrenched in the region. The Persian Samanids (819 – 999) made Islam the official state religion and established a school of theology in Bukhara. But Islamization did not take place overnight; instead, it took centuries. Transoxiana slowly Islamicized, though it never Arabized. The peoples in the area remained culturally Turkic and Persian. Central Asia retained its Turkic and Persian languages, albeit with a heavy Arabic influence in religious vocabulary.
It took generations for Islam to become fully ingrained in the culture of Central Asia. Unlike other places, where the religion filtered into society from the bottom up, as was the case in Southeast Asia, Islamization in the region occurred from the top down. The process incorporated native peoples, who took part in the process of conversion. Local leaders submitted to the faith in order to maintain their social status and elite position in society. The conquerors offered the Central Asian nobility important positions in the administration so long as they professed Islam, providing the opportunity for the native elite to rule in their own right.
Islam also displayed a remarkable ability to assimilate indigenous Central Asian frontier customs as it advanced through the area, allowing some traditional practices to remain so long as it accelerated conversion. By accepting certain harmless practices in order to Islamicize Central Asia, these Muslims mirrored Christian efforts to Christianize Eastern Europe.
The Islam of Central Asia differed greatly from that which originated in the Arabian Peninsula. This vast region embraced Islam, remaking it into a syncretic faith that was culturally its own. Essentially a sort of mysticism, or folk Islam, Sufism in the area emerged from the fusion of Islamic sedentary civilization and Buddhist nomadic culture. Central Asians were generally receptive and tolerant of foreign beliefs, but in order for the faith to take root in the area, missionaries had to make some concessions to the native, specifically pastoral-nomadic culture. The urban-dwelling and agricultural populations of the region generally accepted Sunni Islam and the law of the Sharia; however, the culture and lifestyle of the itinerant peoples of the steppe did not readily conform to the rigors of Islamic law. Sufism helped convert these tribes to Islam, in part due to its doctrinal flexibility. What arose from the mix of orthodox Islam and Turkic pastoral nomadism was a uniquely Central Asian brand of Sufism.
In this context, Sufis evangelized to groups on the frontier of Central Asia. Actually, Sufi merchants were largely responsible for bringing Islam to the region. Central Asian Sufi orders such as the Yasaviyah established themselves along trade routes in order to reach out to travelers. These missionaries also proselytized to the Turkic communities on the steppe. Meanwhile, the Naqshbandi Order, operating in travel lodges, spread Sufism by ministering to Iranian and Tajik peoples. The followers of these Sufi orders believed that they could better disseminate a form of the faith that was more loving and caring.