From Mecca to Damascus: The growth and dominance of the early Islamic empires

According to early Islamic sources, Muhammad ibn Abdullah had received his first revelation in 610 CE when he meditated near Mount Hira.

At the time, Mecca had become a commercial hub and religious centre that drew Arabian tribes to the Kaaba, which housed tribal idols and generated substantial income for the Quraysh elite.

Early opposition to Muhammad’s teachings arose from both theological disagreement and concerns about the disruption of that economic structure.

Local leaders launched a campaign of harassment and exclusion, which prompted the growing Muslim community to seek refuge elsewhere.

In 622 CE, Muhammad and about seventy of his followers emigrated to Yathrib, which was later renamed Medina, where they established the foundations of an Islamic political community.

There, Muhammad structured the ummah around loyalty to faith rather than tribe, and he secured military alliances and oversaw legal decisions, and he set precedents that blurred the boundary between spiritual guidance and political leadership.

He set out these arrangements in a document known as the Constitution of Medina, which regulated relations between Muslim and Jewish clans in the city.

Over the next decade, he had led expeditions such as the Battle of Badr in 624 CE and the Battle of Uhud in 625 CE, and he had negotiated agreements like the Treaty of Hudaybiyyah in 628 CE, and he steadily outmanoeuvred his Meccan rivals.

This culminated in the peaceful re-entry into Mecca in 630 CE. Before his death in 632 CE, Muhammad had unified most of Arabia under a single religious authority, and he left behind a model of leadership that combined prophetic revelation with statecraft.

Following Muhammad’s death, the Muslim community selected Abu Bakr as the first caliph, and this decision began both a new political institution and a series of territorial conquests.

During Abu Bakr’s brief rule, he defeated Arabian tribes that had renounced Islam, thereby restoring unity to the peninsula.

Under his successor, Umar ibn al-Khattab, Islamic forces launched organised invasions into the Byzantine and Sassanian empires.

Within two decades, Muslim armies had captured Damascus, Jerusalem, Alexandria, and Ctesiphon, placing many important trade routes and fertile provinces under caliphal control.

At the Battle of Yarmouk in 636 CE and the Battle of al-Qadisiyyah around 636 or 637 CE, Muslim forces decisively defeated Byzantine and Persian armies.

The fall of Ctesiphon followed these victories during the Mesopotamian campaign.

By the end of Umar’s rule, the caliphate controlled territory that spanned over 2.5 million square kilometres.

To stabilise this expansion, Umar introduced the diwan, a register of military payments that linked tax collection with service obligations.

At the same time, he founded garrison towns such as Kufa and Basra, where Arab troops settled in separate quarters to preserve unity and religious devotion.

These urban centres were military outposts, administrative headquarters, and transmission points for Islamic customs.

Significantly, Umar maintained existing taxation systems and offered non-Muslims protection in exchange for paying the jizya tax, which allowed for the continued employment of local officials and reduced resistance to Arab rule.

Under Uthman ibn Affan, the caliphate had commissioned a single version of the Quran and had expanded naval operations across the Mediterranean.

The Battle of the Masts in 655 CE appeared to demonstrate the growing strength of the Muslim fleet.

However, accusations of favouritism and corruption weakened his authority and sparked unrest.

His assassination in 656 CE triggered a succession crisis that brought Ali ibn Abi Talib to power.

Although Ali had strong claims through his blood ties to Muhammad, his authority remained contested, and the resulting civil war, known as the First Fitna, exposed long-lasting disputes over succession, justice, and religious legitimacy.

In 661 CE, after Ali’s death, Muawiyah ibn Abi Sufyan declared himself caliph and established the Umayyad dynasty.

He moved the capital from Medina to Damascus, a city that offered practical advantages due to its roads and aqueducts, as well as its proximity to former Byzantine strongholds.

From Damascus, Muawiyah built a centralised administration that retained Arabic as its official language, and it drew on the specialist skills of local officials trained under Roman and Persian rule.

The transition from an elective caliphate to a hereditary monarchy altered the nature of Islamic leadership, aligning it more closely with established imperial norms.

Over the next century, Umayyad rulers oversaw major military campaigns that brought North Africa and the Iberian Peninsula, along with parts of Central Asia, under Islamic authority.

In 711 CE, Tariq ibn Ziyad led Muslim forces across the Strait of Gibraltar and defeated the Visigothic kingdom in Spain.

By 732 CE, Muslim cavalry had reached Tours in modern-day France, where they suffered a setback against the Frankish army under Charles Martel.

Meanwhile, eastern advances reached the borders of India and included fortified zones in modern-day Pakistan and Uzbekistan.

By the mid-eighth century, the Umayyad Caliphate governed an empire, which contained more than 30 provinces and an estimated population between 30 and 50 million.

Arabic increasingly replaced many local languages in official records after the reforms of Abd al-Malik, especially in tax records and government letters.

Coinage carried Quranic inscriptions, and tax policies often favoured Arab Muslims, and mawali in some regions continued to pay the jizya tax.

Architectural projects such as the Dome of the Rock, which was completed in 691 CE, had asserted the caliph’s spiritual authority over Jerusalem and had positioned Islam in visual dialogue with Christianity and Judaism.

The Great Mosque of Damascus, completed in 715 CE, further symbolised the integration of Islamic rule with urban infrastructure.

However, the Umayyads relied heavily on Arab tribal elites and placed restrictions on mawali, or non-Arab converts, which bred discontent among broader segments of the population.

To maintain authority over a large and culturally varied empire, the caliphs generally relied on a multi-level system of local rule.

Each province was overseen by a wali, who reported directly to the caliph and managed taxation and policing, along with military recruitment.

In major cities, Islamic judges (qadis) administered legal cases based on the Quran and hadith, while amirs commanded military garrisons.

As a result, Islamic law operated in tandem with political enforcement, and it built religious rules into public institutions.

Over time, jurists such as al-Awza’i and Abu Hanifa developed Islamic jurisprudence into an organised legal system known as sharia, which regulated contracts, family matters, trade, and religious conduct.

Because Islamic teachings applied across the empire, they introduced a degree of legal consistency, though interpretations varied by region and school of thought.

Core religious duties such as daily prayer and fasting during Ramadan, together with charitable giving (zakat), helped foster religious unity and encouraged social cohesion, especially in newly conquered territories.

Trade routes that linked the Indian Ocean with the Mediterranean largely remained active under Islamic rule, and merchants benefited from legal protections based on Islamic business rules.

At the same time, markets flourished in major cities such as Damascus and Aleppo, as well as in Fustat, where goods from Africa and India, along with China, passed into European hands.

Fustat became a major trading centre that drew a high volume of merchants, though precise figures are uncertain.

Mosques operated as centres of worship and as schools and courtrooms, along with public forums, and their influence extended into the daily lives of Muslims, and it offered both religious instruction and civic guidance.

Despite outward stability, religious and political rifts increasingly threatened the integrity of the empire.

The murder of Uthman and the contested caliphate of Ali, along with the outcome of the Battle of Karbala in 680 CE, where Ali’s son Husayn was killed alongside a small band of loyalists, created a permanent divide between Sunni and Shi’a communities.

While Sunni Islam acknowledged the legitimacy of all four Rashidun caliphs, Shi’a groups rejected the first three and honoured Ali’s descendants as the rightful heirs.

Under the Umayyads, tensions deepened due to views of moral weakness and unfairness in the treatment of mawali.

Discontent often found fertile ground in the eastern provinces, particularly among Persians and Shi’a Muslims who resented their low status.

In 747 CE, a rebellion led by Abu Muslim grew stronger in Khorasan and united different groups under the banner of the Abbasid family, who claimed descent from Muhammad’s uncle al-Abbas.

At the Battle of the Zab in 750 CE, Abbasid forces decisively defeated Umayyad troops, seized the capital, and executed most of the Umayyad family.

One surviving Umayyad prince named Abd al-Rahman I fled across North Africa and established an independent emirate in Córdoba.

Although the eastern Umayyads had fallen, their administrative models and Arabic language policies endured, along with their religious traditions.

Some early sources suggest that as many as 80 Umayyad family members were killed in the Abbasid mass killing, and the Abbasid victory did not erase the achievements of the early caliphates but rather built upon their structures to create an even larger Islamic civilisation.