ORHAN OSMANOGLU cradles a French handkerchief embossed with the letter H. “This is all I have left that’s my great-great-grandfather’s, the caliph’s,” he says. His family has fallen far since those illustrious days. Abdulhamid II lived in a palace, Yildiz, in the heart of Ottoman Istanbul; Orhan lives in a high-rise at the end of an Istanbul bus route. Europe’s royals flocked to caliphal functions, but when Orhan’s daughter married, Turkey’s present rulers stayed away. Worst of all, an Iraqi impostor has stolen the title his family bore for hundreds of years. Abu Bakr al-Baghdadi’s barbaric outfit, Islamic State (IS), promises to restore the caliphate. Does Mr Baghdadi know what he is talking about? For 1,300 years the caliphs, or “successors”, prided themselves on developing the Islamic community the Prophet Muhammad left behind. The Ottoman Empire, which rivalled the Roman one in longevity, came to include not only the Middle East, but north Africa, much of the north Black Sea coast, and south-eastern Europe all the way to the gates of Vienna. Ruling from Istanbul, the caliphs kept polyglot courts, reflecting the multiple religions and races represented there. French was a lingua franca at the Ottoman court; Persian, Armenian and Arabic were also spoken.

The caliphs were far from doctrinaire. Abdulhamid II, who ruled from 1876 to 1909, was one of the more Islamist, but he loved music (forbidden by IS) with a passion. He grew up in a court where the princesses played a piano coated in gold leaf given by Napoleon III, and Layla Hanoum taught the princes the cello. On Thursday evenings he would accompany Sufi masters in reciting the dhikr (rhythmic repetition of the name of God), and his imperial orchestra would play Offenbach on the way back from Friday prayers at the mosque. At state banquets the orchestra would match each course to a different concerto, including some by “Pasha” Giuseppe Donizetti, Gaetano’s older brother, who was the court composer. The last caliph, Abdulmecid II, played the violin, entertaining a mixed audience of men and women at concerts.

Far from reading only the Koran and the Muslim Sunnah, Abdulhamid II had a taste for spy novels and Sarah Bernhardt, the greatest actress of her age, whom he brought several times to his private theatre. “In politics Abdulhamid was conservative,” says Suraiya Farooqi, a professor of Ottoman history at Istanbul’s Bilgi University. “In private, his tastes were distinctly Verdi.” The Ottomans paraded in the latest fashions, often imported from Venice. Photographs in the vaults of the old Ottoman Bank show their clerks in pristine English frock-coats. In 1894 the governor of Smyrna, now Izmir, even banned the baggy trousers worn by mountain zeybeks (militias) because he found them uncouth.

In their efforts to emulate other European rulers, the caliphs commissioned Europe’s leading architects to design new palaces. Abdulhamid II’s father, Abdulmecid I, abandoned the Topkapi Palace, perched on the heights overlooking the city, and moved to the Dolmabahce, a neo-baroque edifice with marble steps that were washed by the waves of the Bosporus. Passengers on liners sailing past could glimpse through the windows its crystal balustrades and its chandelier, the world’s largest, made in Birmingham. “The 19th-century caliph projected himself as a European emperor, like the Habsburgs or Romanovs,” says Mehmet Kentel, the head librarian at Koc University’s Research Centre for Anatolian Civilisations. Money was no object: Abdulhamid II’s descendants are seeking to recover a legacy, excluding his estates, that they estimate at $30 billion.

The iconoclasts of IS sledgehammer human likenesses; the last caliphs fashioned them. Abdulhamid II appointed Pierre Désiré Guillemet, a French painter, and his wife to establish the empire’s first arts school, and Fausto Zonaro, an Italian, as his in-house palace painter. Zonaro’s students included Abdulhamid II, whose paintings are still in the Dolmabahce. In “The Pondering” Abdulmecid II painted his wife Sehsuvar reclining, unveiled, reading Goethe’s “Faust” (pictured above). Another of his paintings, “Beethoven in the Harem”, depicts her unveiled again, playing the violin, with a trio that includes one of his Circassian consorts on the piano and a male accompanist on the cello. The setting, again, is continental, with European furnishings and a bust of Beethoven. Neither the orientalist fantasy of the harem nor the zealously segregated purdah of the capital of IS, Raqqa, are anywhere to be seen.

Nor was Western culture confined to the palace. Abdulmecid I hired two Swiss architects, the Fossati brothers, to renovate the Hagia Sophia—the former seat of the Patriarch of Constantinople that became a mosque and is now a museum—installing a gallery for non-Muslims to observe the worshippers below. They designed the country’s first opera house, its first university and new law courts, which are still in use. A Greek architect, Nikolai Kalfa, designed Abdulhamid II’s favourite mosque, Yildiz Hamidiye. So many playhouses, shadow-theatres and concert halls surfaced in the city that “The Encyclopaedia of Istanbul Theatres” fills three volumes. Despite traditional opposition to football, the last caliph’s son, Omer Faruk, was president of Istanbul’s premier team, Fenerbahce, while the city was under British occupation.

Under the 19th-century caliphs Istanbul became a metropolis of modernisation

Under the 19th-century caliphs, Istanbul became “a metropolis of modernisation”, says Philip Mansel in his book, “Constantinople: City of the World’s Desire, 1453-1924”, which spans the five centuries the Ottomans ruled the city. The first official newspaper, Moniteur Ottoman, appeared in 1831, first in French and then in Ottoman Turkish, as well as Greek, Armenian, Persian and Arabic. Abdulhamid II Westernised oriental concepts of time by erecting clocktowers across his empire, often at the entrance to mosques. He furnished Istanbul with an underground metro, the second in Europe. And he introduced the telegraph, an intelligence service and a rail network. The first Oriental Express steamed from Paris to Constantinople in 1889, almost two decades before the Ottomans completed their pilgrimage railway to Medina.

Ottoman attitudes to religiosity could be disarmingly liberal, too. The caliphs maintained multi-tier legal codes for their different communities. From 1839 Abdulmecid I revamped the legal system, introducing secular law alongside sharia. He gave non-Muslims equal rights with Muslims, abolished the right of the sultan to execute members of his court without trial, banned the slave trade and allowed the opening of taverns, which filled with European painters and composers on court stipends. Diplomatic diaries from the time record caliphal scions enjoying a tipple, particularly of drinks that had not existed in the Prophet’s time and were therefore, according to more liberal readings, permitted. Mahmoud II was spotted sipping champagne at society balls.

Enjoying a tipple

Such practices were not aberrations. Drinking was a fundamental part of the pre-Ottoman early medieval caliphal courts, particularly Tamerlane’s, says Hugh Kennedy, a professor of Arabic at London University’s School of Oriental and African Studies, who is writing a book on their wanton ways. The greatest caliph of all, Harun al-Rashid (786-809), presided over an intellectual awakening and oversaw the translation of Greek Sophists in his House of Wisdom in Baghdad, but also partied with his debauched bard, Abu Nawwas, who composed drinking ditties as well as some of the Arab world’s finest classical verse. Drunken dervishes roam “The One Thousand and One Nights”, compiled during his reign.

Occasionally puritans howled. Caliph Walid II was killed in 744 after allegations he had organised drinking parties in Mecca. But dissolution was mostly taken as par for the course. Selim II (1566-75), who conquered Cyprus and Tunisia, died in a drunken stupor, after smashing his head on his Turkish bath.

For all that, the caliphs could be profoundly reverential. They saw themselves as defenders of the multiple faiths that sought their protection, not just Islam. When Spain’s Christian rulers expelled their Jews, Bayezid, the then-caliph, sent boats to rescue them. Istanbul was an Armenian and Orthodox capital as well as an Islamic one. (In the Ottoman army, too, Iraqis fought alongside Albanians and Chechens.) Obedience was expected: Abdulhamid II is reputed to have slaughtered 30,000 Armenians to suppress a revolt around Adana, on the north-eastern Mediterranean. But those who proved docile and useful were welcome, whatever their origin. Abdulhamid II’s foreign minister for a quarter-century was Armenian, as were the architect of his palace and the designer, along with Jean-Paul Garnier, of the clocktowers that became his hallmark across the empire.

Sisli’s Darulaceze, the hospice for the homeless Abdulhamid II built in 1896, is easily missed. A highway zips past above the Golden Horn, too fast to catch the golden Arabic herald over the mahogany doors. But for those who pause there, the long courtyard shaded with cypress trees offers not just an escape from modern Istanbul’s frenzy but a time capsule of caliphal values. It contains a mosque to the south, and a church and a synagogue, with stars of David, to the north. Even as Orthodox Christians and Zionists were seeking to slough off Ottoman rule and govern themselves, the caliph was still building them holy places.

Ultimately, of course, the caliphate, along with eastern Europe’s other dynastic empires, the Habsburgs and Romanovs, was dissolved. After the first world war the British and French occupied Istanbul, along with all the caliph’s remaining Arab lands. Turkish nationalists under Mustafa Kemal, an army general, took the Anatolian rump that remained. Had Russia not fallen prey to its own revolution, its army too might have held eastern Anatolia.

By that point, the caliphs were powerless. In 1923 Mustafa Kemal abolished the Ottoman Empire, proclaimed a republic and made himself president. A year later he abolished the title of caliph. Even a titular role was too threatening for the republicans—and for the British, who feared that a Muslim revival in the Middle East might have repercussions for their rule in India. He stripped the imperial family of its Turkish nationality and possessions, took the Dolmabahce for himself and went on to proclaim himself “Ataturk”, father of the Turks.

Turkish history books ridiculed the country’s former leaders as anti-Western, anti-women, tyrannical and obscurantist. The family lived in penury, strewn across the world. Two became taxi-drivers in Beirut; another played the zither in Lebanese nightclubs. Only half a century later, in 1974, did Turkey let the first male relatives back. Mr Osmanoglu returned from Damascus, recovered his Turkish nationality in 1985, and opened an import-export business trading with bits of his forefathers’ former empire. When Hosni Mubarak was toppled in Egypt, thugs broke into the ports and pillaged his containers, leaving him bankrupt.

Recently, under the Islamist-leaning president, Recep Tayyip Erdogan, Turkey has seemed to relent a little. Textbooks are less derisive. State television sometimes shows interviews with members of the clan. Mr Erdogan is pushing the country to reconnect with its Ottoman past. “Over the last decade people have begun to respect us more,” says Mr Osmanoglu. The day your correspondent met him he had come from Bursa, a four-hour drive away, where he had taken part in the opening of the mausoleum of Murad II, an ancestor who ruled in the 15th century, before the Ottomans had even taken Istanbul. Still, he worries about raising his profile too much, lest Mr Erdogan covet the caliphate for himself. “If the Christians can have their pope, why can’t we have our caliph?” asks the curator of Abdulmecid II’s study in the Dolmabahce.

Mr Osmanoglu has toyed with forming a political party, if only he had the money. The last Ottoman leader stood for election in 1922, he notes, winning office for the first time in six centuries by the people’s formal consent. Perhaps, he says, a little nostalgia for the family and the stability they brought the region remains.

In one of his last paintings, Abdulmecid II depicted a history tutorial. On the table lies a map of Rumelia, today’s Balkans. The tutor covers his face with his hand, too grief-stricken or embarrassed to account for its loss. A ginger-haired girl stares at the map and a boy in a starched collar, cravat and suit points at it, determined to win it back. Beneath the frame, the caliph has added the caution: “Forget those who have caused you personal problems, but don’t forgive the insult to your homeland.”

When Mustafa Kemal dissolved the caliphate, the guards sent to give the household their marching orders are said to have found the caliph in his study beside his easel, perusing volumes of his favourite magazine. It was La Revue des Deux Mondes, exemplifying the Ottoman knack for straddling two worlds that has created such problems ever since. Within 24 hours he had boarded the Orient Express at Stambouli station, heading west to Europe.