The Ottoman empire was home to many nationalities and religions - a cultural mosaic that was splintered by nationalism and war in the 20th Century. But a new spirit of tolerance may be emerging in modern Turkey, albeit slowly and unsteadily, reports Thomas de Waal.
For almost 90 years, the monastery of Soumela, situated at eagle-height in a gorge in eastern Turkey, has been an echoing ruin.
Worship ended here in 1923 when modern Greece and Turkey exchanged their Christian and Muslim populations and the local Christian Greeks from this region left en masse.
Musicians lead a group of pilgrims up the path to the monastery
But in the last decade, Greek pilgrims, calling themselves tourists, have started coming back here on the old feast-day of the Virgin Mary.
Last August I was at the monastery, officially a state museum, as a Greek Orthodox service sounded out again outside its walls but it lasted just 30 seconds.
A black-cassocked monk began to sing the liturgy in deep tones before a Turkish museum curator broke up the service. A fight threatened to break out. The gathering broke up in recriminations and grandstanding speeches.
One step forward, one step back. The story of the-service-that-wasn't at Soumela is a suitably Byzantine tale that takes in Turks, Greeks and Russians and plenty of different factions amongst them.
The background to it is that the government of the moderately Islamic AK Party is challenging tenets of the modern secular Turkish state and reviving memories of the multi-ethnic Ottoman era.
The new foreign policy of "zero problems with neighbours" is building bridges with old enemies, including Armenians and Greeks and that has been welcome for curious Black Sea Greeks who want to revisit the old homeland which they call the Pontus.
Musicians have led the way. Both the Black Sea Turks and the Pontic Greeks play an instrument they call the kemenje or lyra and in English you might call a lyre.
Adem Erdem, a Turk, has performed and recorded in Pontic Greek
It is small, light and three-stringed, made of cherry-wood, played with a bow and held against the knee. Its visceral music sets the rhythm for the round dances that both Greeks and Turks seem to know instinctively.
Two musicians in particular, the Greek anthropologist and lyre-player Nikos Mikhailides and Adem Erdem, a local Turkish player, have blazed a trail.
The album they recorded together in the Pontic Greek dialect has become a smash hit with Pontic Greeks from Thessaloniki to Tashkent. Although not on sale in Turkey, it has been a hit too in Trabzon in thousands of pirate copies.
One of the secrets of this part of Turkey is that tens of thousands of local Muslims, whose ancestors were once Christian, still speak and understand this archaic version of the Greek language.
Trabzon is more famous to English ears as Trebizond, the city of Rose Macaulay's novel The Towers of Trebizond.
Nowadays Macaulay's magical city is a functional Turkish Black Sea port. But last August its past stirred into life again. The day before the feast-day of 15 August, half the valley seemed to be talking Greek.
At a Turkish wedding feast we watched a middle-aged blonde woman with a string of pearls round her neck step smoothly into the dance. It turned out she was a professor of law at Athens University. We were the strangers here, not her.
The next morning we ascended the valley to Soumela.
It was a heady Alpine summer's day. From a distance it could be a Tibetan monastery, a yellowing beehive high above the gorge. Hundreds of people toiled up the path.
The atmosphere was both excited and tense, with watchful Turkish policemen at every corner. Outside the monastery gate, a Greek lyre-player with a fine set of pointed moustaches was whipping a crowd of dancers into a festive frenzy.
The beaming Sotiria Liliopoulos had come from Earlwood, New South Wales - her father, now aged 98, was born in Maçka and came here as a child. In an accent veering from Greek to Australian, Sotiria said, "This is the happiest day of my life."
But politics was humming in the background.
Greeks stopped to venerate the icon carried by a Russian priest
A wealthy member of the Russian parliament of Greek descent named Ivan Savvidi, who is making a pitch to be the leader of the Pontic Greek community, had chartered a ferry to ship Russian Greeks here across the Black Sea.
The nationalist local authorities in Trabzon were nervous of his intentions. When Savvidi's Russian party made it to the top of the path, they were an incongruous mix - there were attractive young women in yellow T-shirts and baseball caps with Byzantine eagles on them, and a bearded man dressed in white shirtsleeves and shades (a priest ordered to remove his cassock) carrying a large icon, which Greeks stopped to venerate and kiss.
The politician himself waved to the crowd and persuaded a Greek priest to start a service.
The priest began to sing, but the Turkish museum curator had orders to stop any religious ceremony on her territory. She pushed out of her ticket booth into the crowd, shouting in Turkish, and tried to wrest a lighted candle out of Savvidi's hands.
Ivan Savvidi, in the yellow tie, is making a pitch to be the leader of the Pontic Greek community
Greek and Turkish television cameras whirred. The divides between the Greeks came to the surface. Some of them, the radicals, started a provocative rendition of the Greek national anthem. Others shushed them.
There seemed to be only two winners here, the Turkish curator and the Russian MP, both of whom had played heroes to the cameras.
Standing on a wall, Savvidi told the Greek crowd that the Turks had offended civilisation and he would complain in Brussels.
He said that he had informed the Russian foreign ministry of his plans, but failed to mention if he had permission from the Turkish government.
As Savvidi spoke, other Greeks - ones who have spent years quietly building bridges with the locals - were drifting away, angry at the way the feast day was being taken from them.
At the bottom of the valley, my mood lifted again. The lyra-musicians were performing and a couple were dancing in extravagant rhythms. The crowd clapped and whooped.
Music is irrepressible and it draws people together, even when the politicians cannot manage it.
Tom de Waal presented Songs of Trebizond on BBC Radio 3 on Sunday, 31 January. You can listen to it on
He is a specialist on the Caucasus with the Carnegie Endowment in Washington.
staff photographer at Swarthmore College, Pennsylvania, USA.