Several different denominations and sects of Islam are practised within Syria, whom collectively, constitute approximately 87% of the population and form a majority in most of the districts of the country. The Sunni Muslims make up the vast majority in the country. The Alawites are the minority group (10% of the country's population), followed by Shia Ismailis. Christians are the main non-Muslim group in the country, they comprise 10% of the population . The Sunnis are mainly of the Hanafi and Shafi'i madhhabs. Some Sufi orders are active in the country, including the Naqshbandiya, the Qadiriya and the Shadhiliya. Sufi numbers have significantly decreased since the turn of the century, most sufis identify as sunni. Although not traditionally considered as Muslims, the Druze make up 3% of the total population. History In 634–640, as part of the Muslim conquest of the Levant, Syria was conquered by the Muslim Arabs in the form of the Rashidun army led by Khalid ibn al-Walid, under the overall leadership of Abu Bakr, resulting in the region becoming part of the Islamic empire. In 635 Damascus surrendered, its inhabitants being promised security for their lives, property, and churches, on payment of a poll tax. It led to Muslim Rashidun control over the entire Levant and brought about major changes to Levantine religious, cultural and social fabric that continue to this day. Until then, Syria was the main center of Eastern Orthodox Christianity. Conversion to Islam had scarcely begun prior to the invasion, apart from Arab tribes already settled in Syria; except for the tribe of Ghassan, these all became Muslim. The loyalty of his new subjects was paramount to the success of Muslim rule in the region, therefore excessive taxation or oppression was avoided. In the mid-7th century, the Umayyad dynasty, then rulers of the empire, placed the capital of the empire in Damascus. As in other areas conquered by the Arabs, the spread of Islam was also accompanied with the spread of Arab culture, which culminated in the Arabization of the Levant and the replacement of Aramaic with Arabic. Throughout Syria's Islamic history, the region was a province of many Islamic empires, formed of various ethnic and Islamic sects. The first successors to the Sunni Umayyad rulers were also Arabs, including the Iraq-centered Abassids (Sunni rulers) followed by the Egypt-centered Fatimids (Shia rulers). Several non-Arab Islamic empires also ruled Syria whilst centered in Egypt