In the year A.D. 610, while meditating in a mountain cave above the town of Mecca, a 40-year-old Arab merchant named Muhammad ibn Abdullah saw a strange vision: An angel, Gabriel himself, commanded him, "Recite!" Stunned by what he saw, Muhammad fell to his knees in confusion. But the angel implored him again. "Recite!" the voice demanded.
It was an odd request of an illiterate man whose life had until then been defined not by godly pursuits but by his far more earthly talents as a businessman and mediator of tribal disputes. "What shall I recite?" Muhammad replied. To which the angel said, according to the Koran: "Recite in the name of your Lord who created, created man from clots of blood! Recite! Your Lord is the most bountiful one, who taught by the pen, taught men what they did not know."
The jolting message Muhammad carried to his fellow Meccans: The collections of idols they and their ancestors had worshiped for generations were false. And, as has been shouted ever since from minarets around the globe: "There is no god but God, and Muhammad is his messenger."
At first, the Meccans mocked Muhammad, calling his revelation fakery or the ravings of a madman. But when he announced subsequent revelations that condemned the nonbelievers to hell, their disbelief flared into outrage. Muhammad's one true God was not only an affront to their spiritual beliefs and ancestral heritage; it also threatened Mecca's social and economic order. If Muhammad was right, the tribal way of life, with its hierarchies and rivalries, was irrelevant. One God meant one people. And Muhammad, not the Quraysh chieftains, was its leader.
Under this new faith, the foundation for society was not tribal affiliation but religious brotherhood. It was a radical idea that would unite the warring Arab tribes and create a military and political power base that the Muslims, as they came to be known, would expand far beyond their Arabian roots.
Thanks in part to Islam's message of social justice and tolerance for other religions of "the book" (Judaism and Christianity), combined with growing unrest under the then dominant Byzantine and Persian rulers, the new faith would quickly win converts from Spain to China. Indeed, within a mere two centuries, Muslims would create the largest empire the world had yet known.
While Islam's rapid spread made it the world's fastest-growing religion, the conversion hardly happened overnight. Indeed, in the three years after Muhammad's first revelation, he is said to have convinced but 30 followers, mostly those of his own clan. Meanwhile, they were persecuted by the dominant Quraysh leaders, who forbade them to marry or even trade with tribal members.
But fortuitously, Muhammad was soon called to Medina (then Yathrib) to help mediate a struggle among five competing tribes. The Muslim migration to Medina in 622 marked the seminal event in Islamic history. Called the hegira, it "marks the beginning of a new polity," Jonathan Bloom and Sheila Blair write in their book Islam: A Thousand Years of Faith and Power. "For the first time in Arabia members of a community were bound together not by traditional ties of clan and tribe but by their shared belief in one true God."
Over the next decade, Muhammad worked to convert Medina's pagan, Jewish, and Christian tribes to his new religion. And a succession of raids on passing caravans won him more followers. Eight years after his flight from Mecca, he returned to his hometown with an army 10,000 strong. The Meccans surrendered without a fight, and Muhammad's triumphant army claimed the city for Islam.
But contrary to Arabian tribal customs that usually resulted in the beheading of losers and the enslavement of their families, Muhammad showed remarkable mercy to his Meccan opponents, demanding only that pagan idols be smashed. He didn't force the Meccans to convert to his new religion, but his pardoning of his opponents helped win them over voluntarily.
The resulting consolidation of Muhammad's power was short lived, however, because he died just two years after taking control of Mecca. He had no male heirs and had named no religious successor, or caliph, a void that sparked a power struggle that has dogged the faith ever since. Some considered Muhammad's son-in-law, Ali, to be his rightful heir—they would become Islam's Shiite faction—but another close friend, father-in-law Abu Bakr, was named the first caliph by Muhammad's closest disciples, beginning a long line of Sunni caliphs.
Although he reigned for only two years, Bakr helped unify the Arabs and made way for his successors, who set out to expand the empire in Iraq, Syria, and Egypt, where they easily wrested control from the pagan Sassanians of Persia, and later the Christian Byzantines. Modern scholars say the Arabs' rapid military success owed more to fortuitous politics than to religious fervor. "People were willing to accept the Muslims because they were fed up with the previous rulers," John Renard, author of In the Footsteps of Muhammad: Understanding the Islamic Experience, says of the competing Persian and Byzantine regimes.
Indeed, their armies had become exhausted fighting each other. Factional conflict in Persia had further worn down Sassanian power, while the Syrian and Egyptian subjects of Byzantine rule had become alienated by the religiously intolerant Greek Orthodox priesthood. In contrast, the conquering Muslims didn't require their Christian and Jewish subjects to convert, only that they pay a special tax for their right to practice their own religions.
Nor did the Muslims try to reinvent the political or administrative wheels of the lands they conquered. The Muslim caliphs imposed Arabic as the official language and minted their own coinage, but they allowed those of other faiths to serve as civil administrators within the Islamic state. The policy allowed life to continue largely as it had, and it reduced resentment of the conquerors.
Further, by allowing all members of society to compete for positions in government, "[the Muslims] set up a new social dynamic in which the criteria for selection was based on competence," says George Saliba, a professor of Arabic and Islamic science at Columbia University. "People were allowed to advance according to their talents. And the result was that they [enhanced] the empire's knowledge base."
It had all the ingredients for a sumptuous societal layer cake: a common language and currency to give it bureaucratic consistency and a flourishing polyglot of cultural and religious diversity to give it social spice.
Nowhere was that more the case than in Baghdad's fabled House of Wisdom, which in the late eighth century became the center of learning in the Muslim world. Overseen by the Abassid caliphate, it drew scholars and intellectuals from throughout the empire. Unfettered by ethnic caste or religious dogma, the best and the brightest were given the freedom to explore the frontiers of science and mathematics and plumb the depths of ancient Greek philosophy and literature.
What united this society most, however, was trade, not merely in books and texts, but in all the riches of a vast empire: textiles and steel blades from Persia, silk and gunpowder from China, spices and tea from India. "It would be wearisome to prolong the catalog," John Glubb writes in his book The Life and Times of Muhammad. "Suffice it to say that for five centuries after Muhammad, the Muslims dominated the world both culturally and militarily as completely as Europe and America have done for the last 250 years."
That is not to say, however, that Islam's so-called Golden Age was an unbroken chain of peace and prosperity. Infighting between rival caliphates sent the center of Muslim rule from Mecca to Damascus to Baghdad and then to Cairo, which even today remains the urban center of Muslim life and intellectualism. That is thanks, in part, to the al-Azhar mosque; founded in 970, it is considered by many to be the world's oldest university.
The dawning of the new millennium, however, marked the beginning of the end of the Muslim empire. Although the Christian Crusaders were vanquished in 1187, soon a new, even greater threat converged on the empire's eastern borders. Genghis Khan and his marauding Mongols quickly overran Baghdad, killing 10,000 people. Remarkably, the Mongols themselves eventually fell under Islam's spell, converting to the faith and eventually becoming some of its leading patrons.
Indeed, for all its initial brutality, Mongol rule had several positive impacts on Islamic society, most notably freeing its rule from domination exclusively by its Arab forebears. Thereafter, the seat of Muslim power and trade would shift east, bringing even more riches from Samarkand and China.
Meanwhile, another Muslim power was beginning to stir in what is now Turkey: the Ottomans. Descended from the nomadic tribes that crisscrossed Turkey's Aral Sea steppe, the Ottomans had served as mercenaries to their Arab predecessors in their defense against the Mongol invaders and eventually became converted to Islam.
The Ottoman Empire traced its origins to Osman Bey, a 14th-century Turkish warlord whose conquest of Bursa, a formerly Christian Byzantine city, effectively ended his ancestors' nomadic tradition and laid the groundwork for what would become Islam's longest-lived dynasty. Taking a page from their Abassid predecessors in ninth-century Baghdad, Osman and his successors' conquests of Christian Byzantium left the previous regime's clerks and bureaucrats in place. They channeled the taxes they collected to line the sultans' pockets and to produce some of Islam's most impressive mosques and palaces.
Their expansion was aided, in part, by their pragmatic take on Islamic society, in which the Ottoman state took precedence over all other institutions, even family and religious affiliation. For example, at a time when Islamic fiefdoms in Turkey, Persia, and elsewhere were vying for power in the region, the Ottomans decided against recruiting military leaders and bureaucrats from the ranks of their Muslim brethren and instead created a new institution: the devshirme.
Composed of young Christian boys taken from newly conquered territories, they were essentially slaves to the Ottoman sultans. They were indoctrinated in Muslim religion, culture, and languages, then given the best possible education and channeled into the empire's highest bureaucratic and military ranks. The result was the creation of a social caste free of conflicting loyalties.
"The system was so beautiful in that they only had one allegiance—to the sultan," Islamic historian Esin Atil explains in the PBS documentary Islam: Empire of Faith. "No family, no region, no other ties. . . . Those who were brainy went to the palace schools and graduated into different levels of [political advisers] and governors....Those who were brawny went to the [military]."
With what was now the toughest, most disciplined army in the world, the Ottomans moved to expand their empire. And in 1453, Osman's heir, Mehmet the Conqueror, seized the Ottoman's ultimate prize: Constantinople, the capital of the dying Byzantine Empire. Within hours of breaching the city's walls with the innovative use of gunpowder, Mehmet laid claim to the Hagia Sophia, the city's—and, perhaps, Christianity's—greatest church. He transformed the church into a mosque and renamed the city Istanbul.
Mehmet's successors further expanded the Ottomans' reach, adding Syria, Egypt, and Islam's holiest Arabian sites, as well as portions of Eastern Europe. By the time the sultan Suleiman came to power in 1520, the Ottoman Empire was at its peak. The 10th descendant of Osman, Suleiman was named for the Old Testament's King Solomon, and he set about to reign in a manner no less grand.
In addition to his military conquests in Belgrade and Hungary, Suleiman took advantage of his great wealth to refurbish the Dome of the Rock mosque in Jerusalem. He also commissioned his chief architect to create what remains one of Islam's greatest architectural legacies: the massive Suleymaniye mosque overlooking Istanbul, a vast domed complex that included a hospital, school, and library. When it was completed, Suleiman was so overwhelmed, he boasted, "Oh, Solomon! I have surpassed thee."
Yet for all his power, Suleiman ultimately failed to carry the banner of Islam into the center of Europe. His siege of Vienna in 1529 ended in retreat. And although he vowed to return, he never did. Instead, he became consumed by the same sort of succession battles that had long undermined the Ottoman Empire; one of his four wives, Hurrem, claimed to have learned of a plot by Suleiman's first-born son and heir, Mustafa, to take over the throne. (Hurrem favored her own son, Selim II, for the sultanate.) Suleiman ordered Mustafa's execution and then descended into melancholy. He himself died in 1566, leaving the throne to Selim II, who soon squandered his legacy with sex and alcohol and left the empire to slowly crumble.
The center of global power would soon shift, as the Old World of Europe turned toward the New World across the Atlantic Ocean, eventually leaving the Ottomans in the historical dust. As a religion, Islam would continue to grow, to become the world's second-largest faith. But never again would it hold political or social dominion over the globe.