Standing in front of Egon Schiele’s Reclining Woman with Louis Godart, the curator of the Capolavori dell’ Arte Europea (Masterpieces of European Art) exhibition in Rome celebrating the 50th anniversary of the European Union, I observe that – with all due respect – the subject matter is a bit, er, risqué.

“Why?” asks Professor Godart, an Italian art expert and archaeologist of Belgian origin who is cultural adviser to President Giorgio Napolitano (the show is at the Quirinale Palace, the head of state’s splendid residence). Well, I say, most of the 27 EU member states have sent a landscape, a portrait, an historical scene or a religious painting: Austria has sent a woman with her red-nippled breasts exposed and her legs apart (the model was Schiele’s wife, Edith).

“You mean the painting is sensual? Well, I don’t see anything wrong with that,” Professor Godart says. “Sensuality is part of the European heritage. Besides, if you look closer” (we do) “you will see that the painting is dated 1917 – the woman’s body evokes passion, but that sombre expression on her face surely expresses the suffering of war and destruction. Her splendid body is here, her mind is elsewhere. So here we have a masterpiece which encapsulates both the joys and tragedies of European history.”

When President Napolitano asked the other 26 EU heads of state to choose a work of art to send to Rome for the exhibition – Italy’s contribution to celebrations marking the 1957 signing of the Treaty of Rome, the EU’s founding document – he gave them a free hand. The result is an extraordinarily eclectic mixture that has drawn applause but also raised a few eyebrows.

The Queen, I was told, had had no doubts, firmly telling President Napolitano when he paid a state visit to London in October that the artist to represent Britain was J. M. W. Turner. Tate Britain then chose The Arrival of Louis-Philippe at Portsmouth, 1844, a swirl of smoke and gold that for years was thought to depict Venice but four years ago was found to show the arrival of the French “Citizen King” to visit Queen Victoria – a happy moment of Anglo-French entente.

Inaugurating the show last week, President Napolitano quoted the French historian Fernand Braudel as saying that “every form of art in Europe goes beyond the threshold of its homeland”. He thanked the EU heads of state for loaning “masterpieces emblematic of their history”. The resulting works range from the Stone Age to the 20th century, the earliest work on display being a small, rotund Maltese Neolithic figure from the third millennium BC, the Fat Lady, symbolising motherhood and fertility.

The Classical world is represented by a figure from the Acropolis portraying Kore, the mythological daughter of Zeus and Demeter, and a vase decorated with the story of the Rape of Europa painted by Asteas, an artist at the Greek colony at Paestum in the 4th century BC. It was returned to Italy last year by the Getty Museum after Italian art detectives proved that it had been illegally exported.

No quarrels there – or with Spain’s choice of Velázquez’s View of the Garden of the Villa Medici, illustrating his (and many European artists’) links with Rome, or with Dörer’s Portrait of Jakob Muffel from Germany. But a “grid composition” by Mondrian for the Netherlands, instead of a Rembrandt, Vermeer or Van Gogh? Rodin’s The Thinker for France, instead of, say, an Impressionist? And why, asked Fabio Isman, the art correspondent of the Rome daily Il Messaggero, had Italy opted for Titian’s Portait of a Gentleman, aka Man with Grey Eyes, rather than a Caravaggio, a Michelangelo or a Leonardo da Vinci?

“Well, as for Mondrian, when I talk to Dutch colleagues in the art world, he is the one they talk about most,” Professor Godart says. “Mondrian has become incredibly fashionable again, he has been rediscovered.

“As for France, the French at first suggested an Ingres, because he painted in Rome – here at the Quirinale Palace, in fact. But then President Chirac stepped in and said no, it had to be a Rodin. Not a bad choice, I think: you will notice that I have positioned The Thinker gazing at the Treaty of Rome displayed in a case in the middle of the hall.”

Ah, the hall: in a sense the Quirinale’s Salone dei Corazzieri (Cuirassiers’ Room) is itself Italy’s contribution, with sumptuous early 17th-century frescoes rivalling the Sistine Chapel by Agostino Tassi, Giovanni Lanfranco and Carlo Saraceni, and dating from the days when the Quirinale was a papal palace.

Professor Godart however defends the choice of Titian as “emblematic of the Italian Renaissance. Besides, it highlights Italy’s skills in restoration – when the portrait was recently restored you could see for the first time that the eyes are not grey, but blue. Perhaps it should be renamed.”

It is curious, he admits, that the East Europeans have sent religious works, with Bulgaria and Romania offering icons and saints. “Perhaps they are asserting their Christians roots after Communism.” Estonia opted for Family in the Water,a 1941 oil canvas by Eerik Haamer, painted a year after the Soviet occupation and showing “the fatal moment when the war machines thundered across a small nation”.

But Professor Godart rejects the charge by Vittorio Sgarbi, the Italian art critic, that the show downplays Europe’s Christian art. “Belgium sent Van Dyck’s Lamentation of Christ, Cyprus a superb icon. Besides, we are looking here at 5,000 years of European art, from the Maltese Fat Lady to the Danish artist Per Kirkeby – the only living artist represented. OK, it’s difficult to choose one work to represent a nation, but I think the mix works. It’s a great show.”

The public seems to agree: the exhibition is currently attracting more than 3,000 visitors a day.

Masterpieces of European Art, Quirinale Palace, Rome, to May 20

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