HIS101 logo Introduction to Islam
by Jim Jones, West Chester University of Pennsylvania (c.2012)
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Islam was founded in the Arabian Desert south of Mesopotamia in the early 7th century. Theologically, Islam is the third religion based on Middle Eastern monotheism. In each religion, a prophet revealed additional information about the will of the supreme metaphysical power. The first prophet was Moses, who founded the religion of Yahweh (Judaism) about 1200-1100BCE. The second was Jesus, who teachings provided the basis for Christianity in 30-33CE. The third was Mohammed, who laid the groundwork for Islam. Nowadays, Islam is one of the world's most popular religions and as of 1992, it had the second largest number of followers (935 million) in the world after Roman Catholicism.


Islam developed in the Arabian Desert, in the towns of Mecca and Medina. Both towns were located along a caravan route that ran parallel to the Red Sea coast. At the time of Mohammed's birth, control over this area was in dispute between the Byzantine and second Persian empires, and the sea route along the Red Sea coast was disrupted by their naval conflicts. Trade shifted to the safer land route, enriching towns like Mecca and Medina. Mecca had another source of wealth because it also possessed an unusual black stone (thought to have been a meteorite) that formed the center of a religious site called the Kabaa. Nomadic Arabs who lived in the region came to Mecca to worship at the Kabaa, and made offerings that enabled the local priests to dominate the government of Mecca.

Mohammed was born into one of Mecca's trading families at the time when the Byzantine-Persian wars sparked a trade boom. He married a wealthy widow named Khadijah when he was 25, and became a successful trader himself. Had he done nothing else, his life would have been comfortable and successful, but in 610 when he was about forty, Mohammed began to tell people that he received instructions from an archangel named Gabriel while he rested in a cave on nearby Mt. Hira during the hot afternoons in Mecca. By talking about Gabriel's revelations, Mohammed acquired enemies among people who believed he was a threat to the local religion. In 622, they forced him to leave, so Mohammed followed the caravan route northwest to Medina (called Yathrib at the time), about 200 miles away. Mohammed's journey became a part of Muslim history known as the hijira, and became the starting date for the Muslim calendar. In Medina, Mohammed had more success because unlike Mecca, Medina's population was settled in camps populated by people from different ethnic groups. Most disputes were settled by the leaders of each group, but disputes between ethnic groups risked escalating into war. Mohammed was successful at settling disputes between ethnic groups, and the people of Medina came to accept him as a leader. As Mohammed's influence grew, he and his followers raided caravans headed to Mecca. After a series of victories and defeats, an army from Medina entered Mecca in 630 and Mohammed was able to return. Unfortunately, Mohammed died in 632 before he named a successor, and that led to the first major dispute in Muslim history.


Islam is a strict monotheism, which means it recognizes only a single deity. The word Islam means "submission" (to the power of the supreme deity) and the basic statement of Islamic faith is "there is no god but Allah, and Mohammed is his prophet." Although Judaism and Christianity are also monotheisms, the Jewish population of Medina refused to recognize Mohammed as a prophet, and Mohammed considered Christianity to be a polytheism because Christians worshipped both God and Jesus. However, Mohammed said that Allah told Muslims to accept Jews and Christians as "people of the book" because they accepted the Old Testament as scripture inspired by the supreme deity. Mohammed conceived of Islam as a means to remove corruption from Christianity and Judaism.

Compared to Christianity, Islam was a simple religion. Islam has no official clergy, although people who demonstrated greater knowledge of Mohammed's teachings are treated as religious leaders. The scripture of Islam is contained in the Koran, which contains the teachings of Allah that were revealed to Mohammed by the archangel Gabriel, although Muslims also accept the validity of the Old Testament. The basic beliefs of Islam are called the Five Pillars of Islam. First, there is the Shahada, which requires believers to recognize Allah as the supreme deity. Believers must also make five daily prayers to Mecca, give charity to the poor, and fast during the month of Ramadan. Finally, every Muslim must visit Mecca at least once on a trip known as the hajj. Although it was not required by Allah, there is a potential sixth pillar called jihad which refers to efforts made to convert others to Islam.

Islam was more than a religion; it was a guide to life. The Shari'a, which combines elements from the Koran, Mohammed's life, and assorted legal precedents, is the basis for Islamic laws that address not only criminal behavior, but also supply a complex code of ethics. For instance, the offenses of wine-drinking and lying (bearing false witness) are related because both distort reality (drunkenness leads to hallucinations). Among many other things, the Shari'a also contains rules for the treatment of women that seem barbaric by modern Western standards, but were considered progressive by the standards of the 7th century. According to the Shari'a, a husband is obliged to support his wife, and could not have more than four wives. The Shari'a also provided a formal means of divorce, which allowed a woman to escape a brutal husband, at least in theory.


When Mohammed died before naming his successor, a struggle for the control of Islam ensued. Mohammed had already introduced the idea of the ulema or council of religious scholars to interpret law, and they took charge of deciding who was best suited to become the next leader of Islam. They chose Abu Bakr, Mohammed's best friend and the father of Mohammed's second wife, but Mohammed's son-in-law Omar (also spelled Umar; married to Fatima) resisted. After Abu Bakr took the title of caliph (meaning "leader, successor and deputy" of Mohammed), he united Muslims by unleashing a jihad against non-Muslims in the Byzantine and Persian empires. When Abu Bakr died in 634, the ulema chose Umar to become the next caliph.

Umar was assassinated in 644 and the ulema chose Uthman, a member of the powerful Ummayyid family of Mecca, as the next caliph. After Uthman was assassinated in 656, his cousin Ali took over, but faced opposition from those who believed that he had assassinated his cousin. Ali was assassinated himself in 661, and another member of the Umayyid family, Mu'awiya (661-680), became the next caliph. Upon his death, the ulema selected his son Yazid (680-682) and from that point on, the position of caliph became hereditary. Yazid restored stability to Islam, consolidated and fortified Ummayyid power, and passed his position on to his son without opposition. Divisions remained, however, and as a result the followers of the Ummayyids became a majority known as Sunni, while those who believed that the succession of the caliphate should have remained within the family of Mohammed became known as Shi'ite.

Other variants of Islam developed over time. One was Sufiism, which emphasized a more mystical approach to Allah that was rejected by both Sunni and Shi'ite Muslims (compare this to the difference between monks and bishops in Christianity). Sufi Muslims acknowledged Muslim saints called (Awliya) which made more orthodox Muslims suspect them of polytheism. Many other variants developed such as the puritanical Wahhabis of Saudi Arabia, the Druze of Lebanon, and the Alawi (a Shi'ite sect), to name a few.


Islam expanded rapidly thanks to a combination of conversions and military victories. The Byzantine provincial capital of Damascus fell to the Arabs in 636, Jerusalem surrendered in 638, Muslims captured the Byzantine fortress of Babylon (Cairo) in 639, and they occupied the Egyptian port city of Alexandria in 640. Meanwhile, other Muslim forces completed the conquest of the Persian Empire by 651. The Ummayyids established their capital in Damascus in order to reduce the influence of the religious leaders in Mecca, and under their direction, Muslims advanced along the North African coast and developed a navy to fight the Byzantine Empire in the Mediterranean Sea. They also established a new city in 670 at Kairawan in modern Tunisia, located just far enough from the coast to be safe from Byzantine forces. From there, Berber converts carried Islam farther west to Morocco and across the Strait of Gibraltar into Spain, until by 720, the Ummayyids controlled everything south of the Pyrenees Mountains. They even sent an expedition north of the mountains into France, but it was defeated at Poitiers in 732 by a Frankish army led by Charles Martel, the grandfather of Charlemagne.

In 750, the Ummayyids were overthrown by Muslims who supported a new caliph named Abbas. His descendants, the Abbassids moved the capital east from Damascus to Baghdad and the direction of subsequent Muslim expansion shifted in that direction. Islam spread beyond Persia across Asia and south along the East African coast in the 9th and 10th centuries, although an Ummayyid caliph continued to rule in Spain at Cordoba. The Abbassid revolution also inspired imitators, and by 969 a Shi'ite movement that originated in Yemen and Tunisia established the Fatimid caliphate in Egypt with a capital at Cairo.

Both the Abbassid and Fatimid caliphs attempted to use converts (Seljuk Turks in Baghdad; Mamluk captives in Cairo) to strengthen their armies, but wound up losing their authority to military commanders called sultans, much like what happened to the Senate at the end of the Roman Republic. After Mongols invaded western Asia in the 13th century, the Seljuks gained complete control over the army. In the 14th century, another group of Turks succeeded in conquering the Byzantine empire, and the descendants of their leader, Othman, reunited Muslims in the 16th century to form the Ottoman Empire.

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