Recently the Russian film director Alexander Sokurov, whose film about the Hermitage in St Petersburg opens in Britain next spring, told me how the great Russian art museum survived the 20th century. "God's will," he said, looking straight at me, unblinking. A million people died in St Petersburg during the second world war.
Across Europe, art was robbed, bombed or burnt in the war. In Vienna, Gustav Klimt's paintings Medicine, Philosophy and Jurisprudence were stolen from their Jewish owners and appropriated by the state. In 1945 SS troops fleeing the allies, in a valedictory act of destruction, set fire to Schloss Immendorf in lower Austria and the paintings were incinerated. In Berlin, a significant portion of the Prussian state art collections - including works by Botticelli - was burned when a secret storage site was hit (not deliberately) by Allied bombs. Other objects, including archaeological finds in Berlin's Pergamon Museum, were transported to the Soviet Union after 1945 as war reparations. Parts of Berlin's "museum island" are still being rebuilt from wartime ruins.
Other works of art survived miraculously, as if by "God's will". There is something almost unbelievable in the wartime adventure of Titian's Danaë, now in the Capodimonte Museum, Naples. It was seized by Hermann Göring - and somehow the sheer gold beauty of Titian's painting makes you think that Göring saw it as real gold to pillage. In 1945 this Nazi loot was found in a salt mine at Bad Aussee in Austria.
Works of art are not people. What does it matter whether art masterpieces were lost or preserved in a war that killed 50 million people around the world? In September 1936 the Spanish Republic, under attack from the fascist forces of General Franco, appointed Pablo Picasso director of the Prado. Picasso's job was not to run the museum but to remind people around the world that contemporary Spanish art drew inspiration from a cultural history now under threat. The fascists were bombing Madrid.
Picasso's anti-fascist art of this period refers directly to art in the Prado, as if he were gathering, protecting, making new its resources. Guernica is in part a modern version of Goya's Tres de Mayo. Picasso said when he was painting it that: "My whole life as an artist has been a continual struggle against reaction, and the death of art." Guernica itself survived the second world war because it went on tour abroad; it was to spend four decades in exile in New York.
Picasso and the Spanish Republic resisted "the death of art", and so did the National Gallery in London. Saving Britain's Art Treasures, a determined delve into secret wartime history by NJ McCamley, documents the increasingly refined and ambitious alternative storage methods that the National Gallery in particular developed during the war to preserve its collection of paintings by Rembrandt, Botticelli, Turner and Michelangelo: treasures all.
It's a sad and disturbing story - not because the protectors of British art treasures failed; on the contrary, they were massively successful. Churches, old houses and public buildings were of course destroyed. In May 1941 the painter John Piper recorded the wreckage of the House of Commons after it was hit by an incendiary bomb, and to this day, the west side of the Tate at Millbank is scarred by wartime explosions. McCamley says that only one major painting from a London collection - Richard Wilson's 18th-century essay in the violent sublime, The Destruction of the Children of Niobe, owned by the Tate - was burned in the blitz, when a restoration workshop in the West End was hit.
Certain art treasures were lucky to survive first the blitz, then the V1 and V2 attacks on London. The Elgin Marbles, which at the end of the 1930s had been repositioned in the British Museum's Duveen gallery, spent the war in a disused tunnel of Aldwych tube station. Studies after the war, when museums were planning for an atomic conflict, showed that a direct hit by a powerful conventional bomb would have wrecked this supposed shelter.
The Marbles had become the subject of huge controversy just before the war. It was alleged by the sculptor Jacob Epstein, among others, that a recent cleaning of the sculptures paid for by Sir Joseph Duveen had severely damaged them - and paranoia increased when the frieze remained deep in the dark in Aldwych station until 1948, long after the war had ended. Epstein publicly wondered if the frieze would ever go on show again.
Nevertheless, the treasures of the British Museum survived. So did the vast majority of British-owned art masterpieces. No, what is sad about this story is the loss of innocence, the growth of mechanisation and apocalypticism, the rapid change that took place during the early months and years of the war from an amateurish, bungling attitude to one of terrifying state efficiency. In this sense, the story of Britain's art treasures during the second world war is emblematic of other aspects of life during wartime.
The first efforts to save the nation's artworks from harm were very much old school tie; paintings and artefacts were simply taken to stately homes outside London, where it was assumed they would be looked after much as in a museum. Kenneth Clark, director of the National Gallery, expressed quiet complacency about the removal of 222 paintings from his museum to the home of Lord Lee at Avening in Gloucestershire in August 1939: "Lord Lee has made the most excellent arrangements for their safekeeping. From the point of view of temperature, security and invigilation, his gallery is excellent."
The rest of the National Gallery collection, except for a handful of paintings that Clark regarded as worthless copies, was sent to Wales, to the National Library of Wales at Aberystwyth, to Penrhyn Castle outside Bangor in north Wales and to the University of Wales's Pritchard Jones Hall in Bangor. The reports sent by the collection's supervisors in Wales were a lot less complacent. In fact, there were persistent rumours in Bangor of Welsh Nationalist-fuelled Fifth Column activity. This sounds like English upper-class hysteria.
It got fairly intense; reports came back to Clark and the Ministry of Works that the paintings might be in danger from a revolutionary mob. You get the impression that in the early years of the war, these English art experts confused Wales with Ireland in 1916 or Russia in 1917.
In reality, it was the blue blood Lord Penrhyn, owner of Penrhyn Castle - a simulacrum of a Norman castle overlooking the Menai Straits, with a pseudo-Romanesque hall resembling a set for The Adventures of Robin Hood - who caused the bother. He was reported to be always drunk, and to be planning to billet troops there, thus increasing the risk of fire. It quickly became obvious that stately homes were not such great places to store artworks after all.
It was not just that, contrary to the assumptions of 1930s planners, north Wales was quite within range of German long-range bombers (indeed, parts of it were on the flight path to heavily bombed Liverpool); it was also that the whole genteel notion of the house-museum was an antiquated fantasy. Old houses were tinderpiles. At the same time, they were gradually being appropriated for troops, who sat around smoking as they waited for action.
So art went underground. In September 1940 Francis Rawlins, the National Gallery's scientific adviser, scouting for subterranean storage facilities, visited the Manod slate quarry above Blaenau Ffestiniog on the southern edge of Snowdonia. Penrhyn Castle had been built from slate industry money; now the National Gallery turned to the slate quarries themselves. Manod had vast man-made chambers 30m high linked by tunnels and drainage shafts. Five chambers, it seemed to Rawlins, which were no longer worked - as other parts of the quarry were at this time - could be isolated and converted into a secret storage shelter.
This was the autumn of 1940 and the National Gallery, like the rest of Britain's institutions, had moved from genteel muddling through to a new kind of slightly frightening radical thought: the nation's art treasures were being prepared for the end of the world, or for a last stand in the Welsh mountains. It took until August 1941 to convert the slate workings into deep shelters. Purpose-designed squat brick "houses" were built inside the vast chambers to preserve the paintings in atmosphere-controlled, air-conditioned and heated safety, with space for conservation work to go on as normal and even for works to be photographed for scholarly purposes. A lot of the lessons in atmosphere control learned inside a Welsh mountain were later applied at the museum in Trafalgar Square.
The paintings were brought to the quarry by truck. A bridge had to be altered so that Anthony van Dyck's 3.7m tall Equestrian Portrait of Charles I could pass underneath it. The stability of the slate chambers proved not quite perfect; there was one collapse, and a system of constant scrutiny had to be developed. As the war went on, a tradition was introduced of taking one painting a month back to London to go on public display, then returning it to the quarry.
Manod proved so successful that in the 1950s, long after the National Gallery's paintings were back on the walls in London, it was the planned destination of Britain's art treasures in the event of a third world war. Atomic bombs falling on the cities, it was reckoned, would leave Snowdonia as a final refuge. However, plans involved taking pictures there only at the very last minute so as not to cause panic.
This is the troubling payoff to the story: the efficient salvational strategy evolved in wartime continued after the war, as museums - again, like the rest of Britain's institutions - planned for atomic conflict with the Soviet Union. It is amazing to think about this. In 1950, while artists such as Francis Bacon created images tortured by the cold-war world, the Tate was wondering if Aldwych or Piccadilly tube station would be any use as an art shelter in an atomic war. Manod was kept as a "prepared quarry", in the official language, ready to store art treasures against nuclear attack at any minute, into the early 1980s. That was when government plans for nuclear war radically changed, and everything not essential to the survival of the state in its barest military and governmental form was sold off. Art will not survive the next world war.
· Saving Britain's Art Treasures by NJ McCamley is published by Pen and Sword Books.
· Jonathan Jones is writing books on Leonardo da Vinci versus Michelangelo and on Thomas Gainsborough for Granta
