During his lifetime, Muhammad was the spiritual and temporal leader of the Muslim community. He established the concept of Islam as a complete, all-encompassing way of life for individuals and society. Islam teaches that Allah revealed to Muhammad the immutable principles of correct behavior. Islam therefÍÍÍore obliged Muslims to live according to these principles. It also obliged the community to perfect human society on earth according to holy injunctions. Islam generally made no distinction between religion and state it merged religious and secular life, as well as religious and secular law. Muslims have traditionally been subject to the sharia (Islamic jurisprudence, but in a larger sense meaning the Islamic way). A comprehensive legal system, the sharia developed gradually during the first four centuries of Islam, primarily through the accretion of precedent and interpretation by various judges and scholars. During the tenth century, legal opinion hardened into authoritative doctrine, and the figurative bab al ijtihad (gate of interpretation) gradually closed. Thereafter, Islamic law has tended to follow precedent rather than to interpret law according to circumstances.

In 632, after Muhammad's death the leaders of the Muslim community consensually chose Abu Bakr, the Prophet's father-in- law and one of his earliest followers, to succeed him. At that time, some people favored Ali, the Prophet's cousin and husband of his favorite daughter Fatima, but Ali and his supporters (the Shiat Ali, or party of Ali, commonly known as Shia) eventually accepted the community's choice. The next two caliphs (from khalifa, literally successor)--Umar, who succeeded in 634, and Uthman, who took power in 644--enjoyed the recognition of the entire community. When Ali finally succeeded to the caliphate in 656, Muawiyah, governor of Syria, rebelled in the name of his murdered kinsman, Uthman. After the ensuing civil war, Ali moved his capital to Mesopotamia (present-day Iraq), where in a short time he, too, was murdered.

Ali was the last of the so-called four orthodox caliphs. His death marked the end of the period in which all Muslims recognized a single caliph. Muawiyah then proclaimed himself caliph from Damascus. The Shia, however, refusing to recognize Muawiyah or his line of Umayyad caliphs, withdrew, causing Islam's first great schism. The Shia supported the claims of Ali's sons and grandsons to a presumptive right to the caliphate based on descent from the Prophet through Fatima and Ali. The larger faction of Islam, the Sunni, claimed to follow the orthodox teaching and example of the Prophet as embodied in the sunna.

Early Islam was intensely expansionist. Fervor for the new religion, as well as economic and social factors, fueled this expansionism. Conquering armies and migrating tribes swept out of Arabia and spread Islam. By the end of Islam's first century, Islamic armies had reached far into North Africa and eastward and northward into Asia. Among the first countries to come under their control was Egypt, which Arab forces invaded in 640. The following year f86 , Amr ibnn al As conquered Cairo (then known as Babylon) and renamed the city Al Fustat. By 647, after the surrender of Alexandria, the whole country was under Muslim rule (see The Arab Conquest, 639-41 , ch. 1). Amr, Egypt's first Muslim ruler, was influenced by the Prophet's advice that Muslims should be kind to the Egyptians because of their kinship ties to Arabs. According to Islamic tradition, Ismail's mother, Hagar, was of Egyptian origin.

Amr allowed the Copts to choose between converting to Islam or retaining their beliefs as a protected people. Amr gave them this choice because the Prophet had recognized the special status of the "People of the Book" (Jews and Christians), whose scriptures he considered perversions of God's true word but nevertheless contributory to Islam. Amr believed that Jews and Christians were people who had approached but not yet achieved the perfection of Islam, so he did not treat them like pagans who would be forced into choosing between Islam and death. Jews and Christians in Muslim territories could live according to their own religious laws and in their own communities if they accepted the position of dhimmis, or tolerated subject peoples. Dhimmis were required to recognize Muslim authority, pay additional taxes, avoid proselytism among Muslims, and give up certain political rights. By the ninth century A.D., most Egyptians had converted to Islam.

Amr had chosen Al Fustat as the capital of Islamic Egypt because a canal connected the city to the Red Sea, which provided easy access to the Muslim heartland in the Arabian Peninsula. He initiated construction of Cairo's oldest extant mosque, the Amr ibn al As Mosque, which was completed in 711, several years after his death. Successive rulers also built mosques and other religious buildings as monuments to their faith and accomplishments. Egypt's first Turkish ruler, Ahmad ibn Tulun, built one of Cairo's most renowned mosques, the Ibn Tulun Mosque, in 876.

A Shia dynasty, the Fatimids, conquered Egypt in 969 and ruled the country for 200 years (see The Tulinids, Ikhshidids, Fatimids, and Ayyubids, 868-1260 , ch. 1). Although the Fatimids endowed numerous mosques, shrines, and theological schools, they did not firmly establish their faith (known today as Ismaili Shia Islam--see Glossary) in Egypt. Numerous sectarian conflicts among Fatimid Ismailis after 1050 may have been a factor in Egyptian Muslim acceptance of Saladin's (Salah ad Din ibn Ayyub) reestablishment of Sunni Islam as the state religion in 1171. Al Azhar theological school, endowed by the Fatimids, changed quickly from a center of Shia learning to a bastion of Sunni orthodoxy. There were virtually no Ismailis in Egypt in 1990, although large numbers lived in India and Pakistan and smaller communities were in Afghanistan, Iran, Syria, and several countries in East Africa.

Data as of December 1990