Akşemseddin: The Sheikh of the Conqueror

Akşemseddin (1389-1459), born Mehmed Şemseddin, is the Bayrami shaykh whose life sits at one of the great hinges of Anatolian and Ottoman history. As the principal khalifa of Hacı Bayram-ı Velî, he carried the Ankara line of tasawwuf into its most consequential public moment: the 1453 conquest of Constantinople under Sultan Mehmed II, whose spiritual teacher he was, and whose constant companion he was during the siege. The discovery of the tomb of Abu Ayyub al-Ansari (Eyüp Sultan), the Companion of the Prophet buried during the first Arab siege of the city seven centuries earlier, is attributed to him. From that moment Eyüp became, and remains, the spiritual centre of Muslim Istanbul.

He was also a working physician. His Maddetü’l-Hayât (“Matter of Life”) is one of the earliest known texts to propose that contagious diseases spread through invisible living agents, a proposition that anticipates germ theory by four centuries.

His name, Akşemseddin, “the white Shams al-Din,” refers to the early whitening of his beard, which the tradition reads as a sign of inner illumination preceding outer years.

A Life from Damascus to Göynük

He was born in 1389 (or 1390 by some sources) in Damascus. His given name was Mehmed Şemseddin. The family traced descent to Shihab al-Din al-Suhrawardi, the founder of the Suhrawardi order, and through the Suhrawardis to the Companion Abu Bakr al-Siddiq. He was raised in Amasya, then a major centre of Ottoman learning, where he completed his Islamic sciences and entered religious teaching as a young scholar.

He met Hacı Bayram-ı Velî in Ankara. The traditional account of the meeting is preserved in the Bayrami hagiographies. Akşemseddin arrived as an accomplished scholar who had heard of Hacı Bayram’s circle and meant to test it. He found Hacı Bayram in the marketplace, asking ordinary people for alms. The sight offended his sense of what a Sufi shaykh should look like. He left without presenting himself. As he walked away, the realisation struck him that what offended him was his own pride, not anything in Hacı Bayram. He turned back, was received, and gave up the scholar’s distance for the murid’s discipline.

He spent years under Hacı Bayram’s training in Ankara and Beypazarı. After completing his formation, he was assigned to Göynük in the Bolu region of northwest Anatolia, where he established his own lodge and lived the rest of his life. He died in Göynük in 1459, six years after the conquest, and was buried there. His tomb remains one of the most visited Bayrami shrines in northwestern Anatolia.

The Conquest of Constantinople

Mehmed II ascended the Ottoman throne in 1451 at the age of nineteen. He had inherited from his father, Murad II, a determination to complete the conquest of Constantinople that had defeated Ottoman attempts since the early 14th century. He had also inherited Akşemseddin as his spiritual teacher.

By 1453 the siege was underway. The sources, both Ottoman chronicles like Aşıkpaşazâde and Tursun Bey, and later Bayrami hagiographies, record that Akşemseddin was at the camp throughout, in close company with the young sultan. His role was twofold: spiritual guidance to Mehmed personally, and assurance to the army that the campaign had divine sanction. In a moment of crisis during the siege, when the conquest seemed to be failing, he wrote to Mehmed a famous letter pressing him not to lift the siege. The conquest came on 29 May 1453.

The first thing Mehmed did after entering the city was to seek out the tomb of Abu Ayyub al-Ansari, the Companion of the Prophet who had carried the Prophet’s standard during the Hijra and who, according to early Islamic tradition, had been buried somewhere outside the walls of Constantinople during the first Arab siege in 674-678 CE, almost eight centuries earlier. The Ottoman tradition holds that Akşemseddin identified the spot. The mosque and shrine complex of Eyüp Sultan was raised at the place he indicated, and from that act the religious topography of Ottoman Istanbul began to be drawn. Every later Ottoman sultan’s accession ceremony involved girding with the sword of Osman at Eyüp Sultan.

Akşemseddin’s relationship with Mehmed was not only of pious counsel. He was free with the sultan when correction was due. The tradition records his frank exchanges with the young conqueror, including moments when he refused royal company in order to keep his own spiritual discipline intact. He returned to Göynük after the conquest and did not seek a place at court.

The Maddetü’l-Hayât and the Physician’s Hand

Less famous in the popular tradition but historically remarkable is Akşemseddin’s medical work. He practised as a physician, and his Arabic treatise Maddetü’l-Hayât (“The Matter of Life”) contains a striking passage on the cause of contagious diseases. He argues that diseases such as plague are not transmitted by miasma (the prevailing ancient theory) but by invisible living agents, tohumlar in his Turkish discussion (literally “seeds”), that pass from the sick to the well. He proposes a careful logic: if the agent were lifeless, it would not multiply; since the disease clearly multiplies as it spreads, the agent must be alive.

This is, in substance, a sketch of what modern medicine would only formalise four centuries later as germ theory. The text predates Fracastoro by a century and Pasteur by four. The claim is sometimes overstated in modern popularisation (Akşemseddin did not have a microscope; he could not isolate or identify any specific organism), but the inference itself is real, and the position is historically remarkable for the 15th century.

His other medical work, Kitâbü’t-Tıb, treats diseases of the era including syphilis, then a new affliction in the Ottoman lands.

That a 15th-century Bayrami shaykh was also a working physician fits the Bayrami doctrine of integrated labour. Hacı Bayram tilled his garden. Akşemseddin tended the sick. Neither saw the contemplative life as separate from useful work.

The Sufi Works

Beyond medicine, Akşemseddin left a small but theologically significant corpus of Sufi treatises. The principal ones are:

Risâletü’n-Nûriyye (“Treatise of Light”), his most cited Sufi work. A defence of Sufi terminology and practice against scholars who had attacked them, written in compact and reasoned prose. He argues that the Sufi vocabulary of states, stations, and inner experience is consistent with the Quran and the Prophetic example, and that the attacks on tasawwuf reflect inadequate understanding of what its terms actually denote.

Hall-i Müşkilât (“Solving the Difficulties”), addressing specific doctrinal questions in Sufi philosophy.

Telhîs-i Def’-i Metâ’în-i Sûfiyye (“Summary of the Defence Against the Detractors of the Sufis”), a polemical work against the critics of tasawwuf. The title indicates its purpose: to summarise the case for the legitimacy of Sufi tradition within Sunni orthodoxy.

The doctrinal voice across these works is consistent with Imam Rabbani’s later formulation in India: Sufi states are real, Sufi practice is legitimate, but the Sharia is the boundary that defines and protects the inner path. Tasawwuf without Sharia is delusion; Sharia without tasawwuf is dry form. Akşemseddin defends the inner science precisely by anchoring it in the outer law.

Place in the Anatolian Silsila

Akşemseddin is the figure through whom the Bayrami line passes from the central Anatolian lodge of Ankara into the founding of Ottoman Istanbul. His own khalifas extended the line in different directions:

Eşrefoğlu Rumi (d. 1469), although primarily Qadiri through his founding of the Eşrefiyye branch, was also a Bayrami disciple and carried the Bayrami imprint into Iznik and the western marches.

Sheikh Mehmed Mübarek and Akbıyık Mehmed Efendi carried the line within Ankara and Bursa.

Sultan Mehmed himself, by the more permissive sources, is counted as a tarikat khalifa of Akşemseddin. By the stricter ones, only as a devoted murid. Either way the Conqueror’s spiritual orientation came from the Bayrami circle.

The Celveti line that would later flower in Aziz Mahmud Hüdâyî and reach into Üsküdar, into the Rûhu’l-Beyân of İsmail Hakkı Bursevî, into the Ottoman religious institutions of the next four centuries, traces back through Üftade Efendi and Hızır Dede to Hacı Bayram. Akşemseddin is the lateral branch of the same root, the one that bent toward Istanbul and the palace, while the Celveti branch later turned back toward Üsküdar and the people. Both branches drink from one Ankara well.

Teaching: Spiritual Discipline at the Threshold of Power

The doctrinal weight of Akşemseddin’s life is that he carried strict Bayrami inner discipline into the highest concentration of political power the Anatolian world had yet produced, and did not allow the proximity to dilute the discipline.

He counselled Mehmed II as a Sufi shaykh, not as a courtier. When his presence at court risked compromising his own adab, he withdrew. His Turkish-language correspondence with the sultan, preserved fragmentarily, is direct, sometimes corrective, never flattering. He held that the prince must rule with the same taqwa the dervish cultivates in the lodge, and that the conquest of cities is permitted to the Muslim ruler only if his own nafs is being conquered inwardly at the same time.

This Bayrami working principle, that proximity to power must not loosen proximity to God, is one of the most consequential gifts the order made to Ottoman political culture. It survived him into the later Ottoman habit of attaching Sufi shaykhs to the imperial court while expecting them to maintain visible independence from it.

Legacy

Akşemseddin’s tomb in Göynük (Bolu province) is one of the most visited Bayrami shrines in northwestern Anatolia. The street and mosque named after him in Istanbul’s Fatih district stand near the inner walls he helped breach. The Bayrami silsila that runs through him is one of the load-bearing structural members of late medieval and early Ottoman Sunni tasawwuf.

His memory is held in two registers in the Turkish religious imagination. In the popular register, he is “the shaykh who took Istanbul,” the discoverer of Eyüp Sultan’s tomb, the white-bearded sage at the side of the young conqueror. In the scholarly register, he is the physician of Maddetü’l-Hayât, the careful theologian of Risâletü’n-Nûriyye, and the Bayrami khalifa who proved that the inner discipline of an Anatolian lodge could meet the largest civilisational moment of its century without losing its integrity.

Yasi was the source. Hacıbektaş was one of the great rooms the source built. Ankara, through Hacı Bayram, was the room from which the next century’s religious architecture would be drawn. Through Akşemseddin, that architecture reached Istanbul on 29 May 1453, and the wells of an inland lodge began to feed the spiritual life of the new Muslim capital.

Sources

• Akşemseddin, Risâletü’n-Nûriyye, his most cited Sufi treatise
• Akşemseddin, Maddetü’l-Hayât and Kitâbü’t-Tıb, his medical works
• Akşemseddin, Hall-i Müşkilât and Telhîs-i Def’-i Metâ’în-i Sûfiyye, defences of tasawwuf
• Aşıkpaşazâde, Tevârîh-i Âl-i Osmân (late 15th c.), the major Ottoman chronicle of the conquest
• Tursun Bey, Târîh-i Ebu’l-Feth (late 15th c.), contemporary court chronicle
• Lâmî Çelebi, Nefehâtü’l-Üns Tercemesi (16th c.), entries on Bayrami silsila
• Sarı Abdullah Efendi, Semerâtü’l-Fuâd (17th c.), Bayrami hagiography
• Ali Ihsan Yurd, Fâtih’in Hocası Akşemseddin (1972, expanded 1994), the principal modern study
• Reşat Öngören, “Akşemseddin” entry in the TDV İslam Ansiklopedisi