Presented by Zia H Shah MD

Prince Karim al-Hussaini, known as Aga Khan IV, served as the 49th hereditary Imam of the Nizari Ismaili Muslims from 1957 until his passing in 2025. Born on December 13, 1936, in Geneva, Switzerland, he was the eldest son of Prince Aly Khan and Joan Yarde-Buller. Educated in Nairobi, Switzerland, and at Harvard University, he was appointed Imam at the age of 20, succeeding his grandfather, Aga Khan III.​ The Lancet

As Imam, Aga Khan IV emphasized the integration of spiritual guidance with practical initiatives aimed at improving the quality of life for Ismaili communities and broader societies. He founded the Aga Khan Development Network (AKDN), which operates in over 30 countries, focusing on areas such as health care, education, cultural preservation, and economic development. Under his leadership, the AKDN became one of the largest private development networks in the world. ​AP News Wikipédia, l’encyclopédie libre

Aga Khan IV was also known for his efforts to promote pluralism and bridge cultural divides. He received numerous honors for his humanitarian work, including the title of “His Highness” bestowed by Queen Elizabeth II. He passed away on February 4, 2025, in Lisbon, Portugal, at the age of 88. His son, Prince Rahim Aga Khan, succeeded him as the 50th Imam of the Nizari Ismaili Muslims.​

The Ismāʿīlī view of the Imamate holds that divine guidance must continue after the Prophet. The Imam (guide) is the ḥujjah (Proof) of God on earth, endowed with the esoteric knowledge (ta’wīl) of the Qurʾān and Sunna and inseparable from the primordial nūr al-Muḥammadī (the Muhammadan Light) inherited from the Prophet’s family ​iis.ac.uk​amaana.org. In other words, each Imam is seen as the living, divinely appointed interpreter of scripture and law, infallible in both spiritual and temporal matters. As Nasir-i Khusraw and later Ismāʿīlī philosophers stress, God never abandons humanity without a guide: in the absence of prophecy this role is fulfilled by the Imam​ iep.utm.edu​amaana.org. The Imam thus embodies the esoteric authority of the Faith – he alone can unveil the inner meanings of religious law. In Ismāʿīlī theology the Imam’s authority is absolute: as Aga Khan IV has emphasized, the Imam “leads in the interpretation of the faith” and serves as a bridge “which links spirit and matter” for the community ​iis.ac.uk​iis.ac.uk. Loyalty (wilāyah) to the Imam is therefore a core obligation, since the Imam is thought to pass on the Prophet’s light and wisdom to his followers.

The Fatimid Caliphate (909–1171 CE)

In 909 CE the first Fatimid caliph–Imam established a new Shiʿi state in North Africa, proclaiming descent from Imam Ismāʿīl ibn Jaʿfar. The Fatimid Caliphate (909–1171) was unique as both a political empire and theocratic Shīʿa regime. The Fatimid Imams (e.g. al-Mahdī, al-Qaʾim, al-Muʿizz, al-ʿAzīz, al-Hākim) ruled as Caliphs while simultaneously claiming the hereditary Imamate. This fusion of spiritual and temporal power allowed them to codify Ismāʿīlī doctrine and law. For example, under al-Qaḍī al-Nuʿmān (d. 974) the Fatimids produced Daʿāʾim al-Islām, the Ismāʿīlī legal compendium that systematically incorporated Shiʿa principles into state policy ​iis.ac.uk.

The Fatimid Imams also patronized major institutions of learning and administration. In 972 Imam‑Caliph al-Muʿizz built the Al-Azhar mosque in Cairo as a center for Shiʿi jurisprudence, and in 1005 al-Ḥākim established the Dār al-ʿIlm (“House of Knowledge”) – effectively the first medieval university, open to Muslims and non-Muslims alike​ iis.ac.uk. The Fatimid state generally practiced tolerance and meritocracy: non-Sunnī Muslims, Christians and Jews could rise to high office on the basis of competence ​iis.ac.uk. These policies reflected the Fatimids’ self-conception as universal Imams upholding justice and inclusiveness. In sum, during the Fatimid era the Imams were sovereigns of a powerful realm, actively promulgating Ismāʿīlī law and theology throughout North Africa, the Levant and the Hejaz​ iis.ac.uk​iis.ac.uk.

The Nizāri State at Alamut (1090–1256 CE)

In 1094 CE a succession dispute divided the Ismāʿīlī community: most North African and Yemeni Ismāʿīlīs followed al-Muʿtansir’s younger son al-Mustaʿlī, but the Persian branch (which Aga Khan IV’s lineage traces) recognized the elder son Nizār as imam ​iis.ac.uk. The Nizārī Imam, Hasan bin Almusta‘nāṣir, fled to the remote mountains of Persia, seizing the fortress of Alamut. Over the next 160 years the Nizārī imams and their missionaries (dāʿīs) constructed a network of impregnable fortresses (in present-day Iran, Syria, Afghanistan) from which they led a quasi-state. Although much smaller than the Fatimid empire, this Alamut period was a time of intense theological activity. Hasanʹs successors (e.g. Ḥassan II, Muḥammad II, Ḥasan ʿAlā Dhikrihī’l-Salām) continued to claim full imamatic authority, albeit with less overt political power than their Fatimid forebears. The Ismāʿīlī of Alamut eschewed expanded warfare at this time and focused on doctrinal consolidation: for instance, they preserved extensive libraries in their mountain strongholds and supported scholars of philosophy, science and comparative religion ​iis.ac.uk. Even amidst conflict with the Seljuks and Crusaders, the Alamut imams maintained a “liberal policy of patronage” (regardless of creed) and continued the Ismāʿīlī tradition of esoteric scholarshi p​iis.ac.uk.

This phase ended in 1256 CE when Mongol forces destroyed Alamut, extinguishing the last Nizārī state ​iis.ac.uk. The Mongol conquest did not end the Imamate itself, but it forced the Imams (and their followers) into diaspora and concealment.

Diaspora and Concealment (13th–18th centuries)

After the fall of Alamut, the Nizārī Imams no longer ruled territory and remained mostly hidden. The line of Imams continued in obscurity, often residing in Persia or Central Asia. During these centuries, Ismāʿīlī communities around the Indian subcontinent and Central Asia remembered the hidden Imam and awaited his guidance. By the 18th century the imam of the Qādirī branch (later known as Aga Khan I) was based in Persia but facing pressure from competing powers. The details of this period are scant in historical records, reflecting the Imams’ low profile. Nonetheless, tradition holds that Ismāʿīlīs of Badakhshān (in the Himalayas) and elsewhere maintained secret allegiance through hujjats (appointed “proofs” or deputies) who taught the ta’wīl and guarded the Imam’s doctrines.

The Modern Imamat (Aga Khan I to Aga Khan IV)

The modern phase of the Nizārī Imamate began in the early 19th century with Hasan Shah (Aga Khan I, nāṭiq style title). In 1817 Aga Khan I was formally recognized as Imam of the Ismāʿīlī community. His era marked a reemergence of the Imamat on the world stage. Settling in India under British protection, Aga Khan I cultivated relations with local rulers and the British Empire. He focused on community welfare and education: for example, Aga Khan II (1830–1885) founded schools in Bombay and elsewhere and served on the Bombay Legislative Council on behalf of Muslims​ iis.ac.uk.

The most transformative reign was that of Sir Sultan Mahomed Shah (Aga Khan III, imam from 1885–1957). As the longest-serving Imam, Aga Khan III witnessed the collapse of colonial empires and the emergence of modern nation-states. He steered the global Ismāʿīlī community through these changes by emphasizing education, social reform and political representation. He established dozens of schools and hospitals, encouraged women’s education, and worked for separate Muslim electorates to secure his followers’ rights ​iis.ac.uk​iis.ac.uk. In 1938 he promulgated the Ismāʿīlī Constitution, laying down the framework for community governance (local councils, schools, etc.) in East Africa and India. In each generation, the Imam’s role has thus adapted: from sovereign ruler in a caliphate to missionary leader in fortress isolation, to in modern times a transnational spiritual and social guide. As Imam III himself noted, the community’s institutions (schools, trusts, hospitals, etc.) built in the early 20th century “became the foundations of the current network of institutions” serving the Jamat ​iis.ac.uk​iis.ac.uk.

Transformation of the Imam’s Role

Over time the nature of the Imamate shifted markedly. In the Fatimid era the Imam-Caliph wielded temporal power and doctrinal authority simultaneously. Under Alamut, the Imam’s political rule contracted but his esoteric authority was maintained and taught by his dāʿīs. After 1256 the Imams lost all worldly dominion; their authority became purely religious and communal. In the colonial and post-colonial era the Imams (Aga Khans I–IV) have had no territorial state, yet they exercise supranational leadership through guidance (farmāns), charity, and development work. In Aga Khan IV’s own words, the Imamate today “leads in the interpretation of the faith” but also builds “bridges” between cultures and peoples ​iis.ac.uk. In practice this means the Imam functions as a global patron of education, culture and economic development (through agencies like the Aga Khan Development Network) while remaining the community’s spiritual guide.

Theological Writings and Institutional Developments

Throughout these periods, Ismāʿīlī scholars produced treatises and founded institutions that reinforced the Imamate’s authority. Under the Fatimids, key works like al-Qaḍī al-Nuʿmān’s Daʿāʾim al-Islām and treatises on ḥujjah and ta’wīl codified the Imam’s prerogatives. The literature of Alamut (the rasāʾil al-nūr, Wajh al-dīn, etc.) expounded esoteric Qurʾānic interpretation under the Imam’s guidance. In the modern era, the Imam’s own farmāns (decrees) and speeches are collected and studied as authoritative sources of doctrine.

Institutionally, the Imamate has established enduring centers of learning and welfare. The Fatimid Imams endowed the Al-Azhar mosque (972 CE) and the Dār al-ʿIlm (1005 CE) as great universities open to all faiths ​iis.ac.uk. The Nizāri Imams of Alamut preserved vast libraries at their castles and maintained networks of dāʿīs. In the 19th–20th centuries, the Aga Khans created schools, hospitals and financial institutions for the Ismāʿīlī community. Notably, Aga Khan III (and later Aga Khan IV) founded teacher training colleges and universities (e.g. a campus of London’s universities in Karachi), mirroring Al-Azhar’s legacy. In 1977 Aga Khan III endowed the Institute of Ismaili Studies in London as a center for research on Shiʿī Islam and the Imamate. Today, the Ismāʿīlī Imamat’s constellation of institutions (from local Jamatkhanas to Aga Khan universities and cultural boards) embodies its commitment to combine spiritual guidance with social progress​ iis.ac.uk​iis.ac.uk.

Sources: Classical Ismāʿīlī texts and modern scholarship emphasize the continuity of the imamatic authority from Muhammad through the Fatimids to the Aga Khans ​iis.ac.uk​amaana.org​iis.ac.uk. The historical narrative above is supported by Ismāʿīlī histories and academic studies (e.g. Daftary, Halm) and by official Ismāʿīlī sources (IIS publications, farmāns, etc.) as cited.