After the death of Muhammad in 632 CE, Islam expanded from a religious community on the Arabian Peninsula into a global faith. Its development spans fourteen centuries, involving political expansion, cultural florescence, internal divisions, and modern transformation. The following overview traces its evolution by stages and analyzes the driving forces behind its growth within each historical context.

1. The Period of the Rightly Guided Caliphs (632–661 CE)

Succession Crisis and the Beginning of Expansion

Muhammad left no designated successor, leading to disputes. Abu Bakr (632–634), elected as the first caliph, suppressed the Riddah Wars (“Wars of Apostasy”), defeated rebellious tribes, and consolidated Islamic unity. He initiated campaigns against Byzantium and the Sassanian Empire, thus beginning territorial expansion.

Umar (634–644): The second caliph greatly expanded Islamic territories, conquering Syria (Battle of Yarmouk, 636), Egypt (642), and western Persia. He established an administrative system with provincial governors, levied the jizya (tax on non-Muslims), and permitted conquered peoples to retain their religions.

Uthman (644–656): The third caliph standardized the Qur’an and codified its official text. He expanded into North Africa and Central Asia but was criticized for nepotism and assassinated in Medina in 656.

Ali (656–661): The fourth caliph, cousin and son-in-law of Muhammad, moved the capital to Kufa (in present-day Iraq). His rule was marked by the First Fitna (civil war) against Muawiyah, governor of Syria. Ali was assassinated in 661 by a Kharijite.

The Roots of Sectarian Division

Ali’s death deepened the divide between: Sunnis, who supported electing caliphs, and Shi‘ites, who believed Ali and his descendants were the only legitimate leaders.

Muawiyah founded the Umayyad Dynasty, ending the period of the Rightly Guided Caliphs.

2. The Umayyad Caliphate (661–750 CE)

Imperial Expansion and Arabization

The Umayyad capital was established in Damascus. Under their rule, Islamic influence reached its greatest territorial extent.

In 711, Muslims crossed the Strait of Gibraltar and conquered Spain (al-Andalus).

Eastward, they advanced into Central Asia (Bukhara, Samarkand) and the Indus Valley.

Their empire stretched from the Atlantic Ocean to China’s borders.

The Umayyads promoted Arab rule and made Arabic the official language, strengthening cultural unity. However, mawali (non-Arab Muslims) resented discrimination in taxation and social status.

Internal Crisis and Collapse

Late Umayyad rule was marked by corruption. During Yazid I’s reign (680), the death of Husayn (son of Ali) at Karbala intensified Shi‘ite resistance. In 749, the Abbasids allied with Shi‘ites and other disaffected groups, overthrowing the Umayyads in 750—although a branch survived in Spain as the Later Umayyad Emirate/Caliphate.

3. The Abbasid Caliphate and the Islamic Golden Age (750–1258 CE)

Cultural and Intellectual Flourishing

The Abbasids moved the capital to Baghdad, ushering in the Islamic Golden Age. Under Caliph al-Ma’mun (813–833), the House of Wisdom (Bayt al-Hikmah) was established to translate Greek, Persian, and Indian works, fostering a scientific and philosophical renaissance.

Major achievements include:

Mathematics: Al-Khwarizmi laid the foundations of algebra.

Medicine: Ibn Sina’s (Avicenna’s) Canon of Medicine shaped European science for centuries.

Philosophy: Ibn Rushd (Averroes) interpreted Aristotle, influencing medieval Christian thought.

Literature & Architecture: One Thousand and One Nights and the architectural splendor of Baghdad flourished.

Fragmentation and Decline

From the 9th century, regional powers emerged, such as:

The Fatimid Caliphate in Egypt (Shi‘ite, 909–1171)

The Later Umayyads in Spain (929–1031)

By the 10th century, Abbasid caliphs retained symbolic authority, while real power lay with: The Shi‘ite Buyids, and later; The Sunni Seljuk Turks.

In 1258, the Mongols sacked Baghdad, destroying the House of Wisdom and ending the Abbasid Caliphate (a symbolic lineage survived until 1517).

4. The Late Medieval Era and the “Three Empires” (13th–19th Centuries)

Ottoman Empire (1299–1922)

The Ottomans rose in Anatolia and conquered Constantinople in 1453, renaming it Istanbul and ending the Byzantine Empire. Under Suleiman the Magnificent (16th century), the empire spanned Eastern Europe, the Middle East, and North Africa, becoming the leader of Sunni Islam.

The Ottomans adopted the millet system, granting Christians and Jews autonomy—promoting multi-religious coexistence.

Safavid Empire (1501–1736)

In Iran, the Safavids established Shi‘ism as the state religion, counterbalancing the Sunni Ottomans. Founder Ismail I claimed descent from Ali and enforced conversion, shaping Iran’s lasting Shi‘ite identity.

Mughal Empire (1526–1857)

Founded by Babur, the Mughals ruled the Indian subcontinent.

Akbar the Great (1556–1605) promoted religious tolerance and abolished the jizya tax.

Aurangzeb (1658–1707) restored Islamic orthodoxy, sparking resistance.

British colonialism ended Mughal rule in 1857.

Global Expansion

Between the 13th–15th centuries, Islam spread through trade and Sufi missionary activity to:

Southeast Asia (e.g., Aceh Sultanate in Indonesia)

West Africa (e.g., Mali Empire)

Sufism’s mystical spirituality (including the “whirling dance”) attracted converts and facilitated cultural adaptation.

5. The Modern and Colonial Period (19th–20th Centuries)

Colonial Disruption

European colonialism weakened Islamic powers: The Ottomans were partitioned (dissolved in 1922 after WWI). The Mughals were replaced by British rule (1857). North Africa fell under French control. Muslim societies confronted modernization and Western influence. Reform and Revival

Key movements included:

Wahhabism: Founded by Muhammad ibn Abd al-Wahhab in the 18th century, advocating a purist Islam; later influential in Saudi Arabia (est. 1932).

Modernism:

Muhammad Abduh of Egypt (1849–1905) argued Islam was compatible with science, publishing al-Manar.

Syed Ahmad Khan founded Aligarh University in India.

Pan-Islamism: Jamal al-Din al-Afghani promoted Muslim unity against Western domination.

Rise of Nation-States

In the 20th century, Islamic states gained independence: Turkey (1923), abolishing the caliphate; Saudi Arabia (1932); Pakistan (1947), founded on Islamic identity

In 1979, the Iranian Revolution established a Shi‘ite theocracy.

6. Contemporary Development (20th–21st Century to 2025)

The Cold War and the Petroleum Era

Muslim countries aligned with different blocs:
Saudi Arabia allied with the United States
Afghanistan became a battleground during the Soviet invasion (1979–1989)

Oil wealth increased Middle Eastern geopolitical influence but also widened internal inequalities.

Extremism and Backlash

From the 1980s:
Al-Qaeda (founded by Osama bin Laden)
ISIS (2010s)

advocated violent jihad. By 2025 their power had greatly diminished, yet their legacy continues to affect conflicts (e.g., the Syrian Civil War).

Globalization and Migration

Large-scale Muslim migration to the West reshaped cultural landscapes:
By 2025, Europe had roughly 30 million Muslims.
Issues like the headscarf debate in France reflect cultural tensions.

In contrast, Southeast Asia (Indonesia with 230 million Muslims) and Africa (Nigeria with 110 million) became centers of population growth.

Summary as of 2025

As of February 26, 2025, Islam has approximately 2 billion followers, making up 25% of the world population. Its history reflects a shift from unified empire to diverse nation-states, from periods of scientific brilliance to modern challenges, exerting a profound influence on global politics, culture, and society.