IN THE spring of 1887 a Lebanese villager named Mohammed Sherif discovered a well near Sidon that led to two underground chambers. These turned out to be a royal tomb containing 18 magnificent marble sarcophagi dating back to the fifth century BC. The Ottoman sultan, Abdul Hamid II, ordered the sarcophagi exhumed, placed on rails and carried down to the Mediterranean coast, where they were sent by ship to Istanbul. The largest sarcophagus was believed to contain the remains of Alexander the Great. The coffin is not Turkish and Sidon is now in Lebanon, but the sarcophagus is regarded as Istanbul's grandest treasure, as important to the archaeology museum there as the “Mona Lisa” is to the Louvre.

The mildly Islamist government of Recep Tayyip Erdogan, led by the Justice and Development (AK) party, likes to think of itself as the heir of the Ottoman sultans. The Turkish authorities have recently launched a wave of cultural expansionism, building new museums, repairing Ottoman remains, licensing fresh archaeological excavations and spending more on the arts. A grand museum in the capital, Ankara, is due to open in time for the centenary of the Turkish republic in 2023. “It will be the biggest museum in Turkey, one of the largest in Europe; an encyclopedic museum like the Metropolitan or the British Museum (BM),” boasts an aide to Ertugrul Gunay, the culture and tourism minister. “It's his baby, his most precious project.”

Turkey's cultural plans at home are coupled with an unprecedentedly bold campaign to bring back treasures that it believes were stolen, which now sit in Western museums. These plans enjoy political support across the spectrum and the backing of all Turkey's museum directors. The campaign targets many more objects and museums than the government has so far let on. “We are not waging a battle,” says Mr Gunay. “But this is definitely a struggle in the field of culture. And we are determined to boost our efforts in a more determined and more persistent way.”

The Turkish authorities are using a mix of entreaty and threats to ensure they get what they want. They are refusing to lend treasures abroad, dragging their feet on licensing foreign archaeological digs and launching public campaigns they hope will shame Western museums. Curators in other countries are alarmed at what they see as growing aggression. A leading museum director even described the campaign as “blackmail”. So what chance has Turkey of winning this new culture war?

At the crossroads of the ancient world, drawing Roman armies from the west and Persian conquerors from the east, Turkey—especially the region of Anatolia—has long been a rich seam of knowledge and treasure from antiquity. In the 19th century teams of European scholars travelled there in search of archaeological remains. Among the most successful was a German unit led by Carl Humann. Armed with a firman, or Ottoman permit, and financed by a group of rich backers in Berlin, Humann and his team, in 1878, began excavating a site in Bergama, near the modern city of Izmir on the Aegean coast of western Turkey.

Humann's most important discovery was the altar of Zeus, which dates from the second century BC. Its dramatic frieze depicting the battle between the giants and the Olympian gods makes it one of the most distinctive works from the classical world. With the sultan's permission, the altar was sent to Germany and became the centrepiece of the Pergamon museum in Berlin. Meanwhile, German archaeologists continued to work on the site; today, the ancient city of Pergamon is the second oldest ongoing archaeological dig in the world. German excavations are still the most important of the foreign digs in Turkey, and for decades Turkish archaeologists have been educated in Berlin and other German cities, their studies subsidised by German government grants.

Archaeological teams like Humann's were soon followed by scholars from Britain and France, and into the 20th century from Italy, Japan and America. Some paid for their projects by selling a portion of their finds to Western collectors who were becoming increasingly enamoured of all things à la Turque. Others removed treasures they believed might be at risk from war and insurrection, and gave them to the new European museums. Foreign scholars saved a considerable number of Turkish artefacts from being commercially looted or destroyed by invading armies. This is rarely mentioned in Turkey's discussions about its archaeological past.

The precise way in which objects were acquired has kept on changing. Some scholars had formal permission from the Ottoman authorities to take their treasures back to Europe; others were motivated by a wish to preserve and protect and did not bother with obtaining proper permissions or establishing a full and accurate provenance for an object. Looters robbed graves and helped themselves.

Use of force

Western museums house tens of thousands of objects from Turkey. Most of these were given or acquired without full documentation. Though Turkey passed a law in 1884 (updated in 1906) stating that all antiquities were the property of the state and could not be taken out of the country, this was only loosely enforced. For most of the 20th century Turkish authorities were happy to lend their treasures for foreign exhibitions and ignored the provenance of most pieces in Western collections. Today, however, the government argues that any object without the correct permissions or with gaps in its provenance has been stolen and so belongs to Turkey.

Growing economic power and stalled talks over EU membership make many Turks feel that it is time to turn their backs on the West. Amid the turmoil of the Arab spring Turkey believes it can become the leader of the region. “A new Middle East is about to be born,” Ahmet Davutoglu, the foreign minister, told parliament last month. “We will be the owner, pioneer and the servant of this new Middle East.”

Turkey has been inspired by the success of Italy and Greece in confronting the illicit trade in classical antiquities. Officials also cite the tough stance taken by Zahi Hawass, a colourful former Egyptian minister, against museums with dodgy holdings. “We will make life miserable for museums that refuse to repatriate,” he pronounced at an international 2010 conference in Cairo about looted artefacts.

Turkey has been emboldened by two important successes. Last September the Boston Museum of Fine Arts bowed to public pressure and returned the top half of an 1,800-year-old statue called “Weary Herakles”, which came from southern Turkey. Left to the museum by an American couple, its documented provenance went back no more than 30 years, which suggests it was looted, probably in the late 1970s. Mr Erdogan himself brought this trophy back to Turkey, reuniting the head and torso with the statue's bottom half.

The sphinx-like Mr Gunay Mr Gunay also forced the German government to return a massive sphinx (pictured) that had been removed in 1917 from Hattusa, the Bronze-Age capital of the Hittite empire. The sphinx is one of a pair. The first was sent back to Turkey in 1924. Its twin had long been part of the permanent display at the Pergamon museum in Berlin. Germany maintained it had obtained the sphinx legally, whereas Turkish authorities argued that it had merely been sent to Germany for repair. Documentation about the sphinxes was destroyed in bombing raids on Berlin in the second world war. Early last year Turkey stepped up the pressure, indicating that it would not renew the licences of the German archaeology institute, the biggest foreign group working in Turkey, unless the sphinx was sent home. In May 2011 German and Turkish culture officials signed an agreement to return the sphinx as part of a wider accord on training curators, exchanging research and enabling loans of Turkish objects. But German curators now complain that as soon as the sphinx went back to Turkey the rest of the agreement was quietly shelved. The Turkish authorities then turned their attention to the Metropolitan Museum of Art. In September 2011 a delegation led by Murat Suslu, the director-general for cultural heritage and museums, flew to New York to discuss loans for a 2014 exhibition. Mr Suslu, who has a reputation as a table-thumper, opened the meeting with a declaration of intent. Before any further loans could be discussed, he wanted information about 18 works in the Met's collection. “It certainly came as a surprise to us,” says the Met's director, Thomas Campbell, “especially in light of the collaborative spirit we have always enjoyed with our peer institutions in Turkey.” Within weeks, the focus was on the BM. The Topkapi Museum had agreed to an important loan for an exhibition about the Haj that the BM was planning for January 2012. The 35 pieces under discussion had been removed from Mecca by the Ottoman authorities in the 19th century. At the last moment, Mr Suslu and Mr Gunay refused to allow the loan to go ahead on the grounds that the BM had a stone tablet dating from the first century BC, known as the Samsat Stele, that originally came from Turkey. The stele had been in the BM's collection for almost 90 years (and had been exhibited, without complaint, at a Tokyo exhibition in 2005 alongside loans from the Topkapi). The BM says that the stele entered its collection in 1927, nine years after the collapse of the Ottoman empire, and it had been acquired in Syria, not in Turkey. The Turks were unimpressed. “The British Museum has no sense of joint venture,” says Ilber Ortayli, head of the Topkapi. “They were completely unco-operative.”

Shock, not awe

Turkey has many other museums in its sights. A list of artworks being sought abroad indicates the culture ministry has made similar demands of the Louvre, the Pergamon, London's Victoria and Albert Museum (V&A), the Gulbenkian Museum in Lisbon, the Davids Samling Museum in Denmark, the Dumbarton Oaks Museum in Washington, DC, the Cleveland Museum of Art and the Getty. It has also claimed stolen antiquities that have been seized by police in Frankfurt, Florence, Bulgaria, Switzerland and Scotland.

Museum directors have reacted with varying degrees of shock. Some have instructed lawyers; others, such as the V&A, are hoping that a “long-term” loan of the contested object will satisfy the demands from Ankara. (Mr Gunay says only an “indefinite” loan will suffice.) Still more are prevaricating, hoping that the authorities will lose interest. This is unlikely.

Turkey is convinced of the justice of its quest. Moreover the culture ministry lumps together objects that were smuggled out of the country illegally with those that were removed—perhaps legally to a place of greater safety, but not provably so—in an era when ownership was judged in a looser way. For Turkey, all of these objects were stolen. It is determined to get them back.

Mr Gunay's ministry is beefing up its anti-smuggling and intelligence bureau, and will soon add criminal and legal units to its task force. Easy foreign travel, communication and technology have all helped the restitution campaign. Turkish émigrés and Turks travelling abroad have helped to identify objects in foreign museums. Online museum inventories, with details of acquisition and provenance, are another rich source of information. The ministry is also working with the American group behind WikiLoot, a not-yet-launched effort to use crowd-sourcing to combat the illicit antiquities trade.

Turkish self-justification is as romantic as it is defiant. Asked about the return of the sphinx of Hattusa, which he personally oversaw, Mr Gunay explained that it went to a museum in Corum, “the very homeland of the sphinx”. He added, “I wholeheartedly believe that each and every antiquity in any part of the world should eventually go back to its homeland. Even if these objects are made of stone, just as people have souls, so do animals, plants and monuments. Taking a monument away destabilises the world and is disrespectful to history.”

These arguments are selective. Turkish officials refuse to concede that Turkey itself, over centuries of domination, forcibly removed hundreds of objects from their homelands. Asked whether Alexander's sarcophagus would be returned to Lebanon, Mr Gunay and his interpreter simply ignore the question. The Turks are too determined to depict themselves as victims of cultural oppression to accept that foreign museums and archaeologists have also played a part in saving their treasures.

The result is an impasse. Foreign museum directors wish to keep ties with Turkish museums, but if all objects from antiquity were to be repatriated to their land of origin, as Mr Gunay suggests, what justification is there for institutions such as the Met, the Louvre and the BM? Why, for example, should the BM retain the Parthenon marbles in London? The carvings were acquired by Lord Elgin when Greece was part of the Ottoman empire. Lord Elgin had obtained a firman, or Ottoman permission from the local authorities, but only after the payment of significant bribes. Does that make acquisitions illegal?

Turkey's campaign has strong support at home. But counting any object acquired without a distinct contract as stolen should alarm museums everywhere.