The best of Blake from Albion and beyond

The poet and artist's greatest works have been brought together at Tate Britain. Louise Jury reports

When the biggest ever exhibition of William Blake's work opens at Tate Britain this week, it will reveal the gems of the great visionary's art.

When the biggest ever exhibition of William Blake's work opens at Tate Britain this week, it will reveal the gems of the great visionary's art.

The world's art stores have offered up their treasures for an exhibition which the curators, Christine Riding and Robin Hamlyn, believe may never be bettered. While the reputation of the finest British galleries can increasingly secure the most prestigious of loans, the feat is particularly impressive in the case of Blake, whose fragile works, on paper and in the notoriously unstable medium of tempera, are at significant risk of damage when moved. Some of the 639 items on display are rarely loaned. To borrow one work, Sir Jeffery Chaucer and the Nine and Twenty Pilgrims on their Journey to Canterbury, from Pollok House in Glasgow, a conservator was dispatched to Scotland to carry out vital stabilising work before it could travel. Another, The Sea of Time and Space, is usually held at Arlington Court, the National Trust property in Devon where it was discovered on top of a wardrobe in the 1930s, but it has been allowed out for the Tate show.

The Yale Centre for British Art in the States, founded by the late philanthropist Paul Mellon, has lent the only existing full colour edition with all 100 plates intact of Blake's prophetic poem, Jerusalem. "They felt this was the Blake exhibition and if it was going to be lent, it should be to us," Riding says. "It has probably not been seen in this country as a complete item in the 20th century. It is one of the great moments in the exhibition."

For a show on this scale, the number of lenders is comparatively small - 46, all from Britain, Australia and the United States, compared with, say, 65 for the recent Ruskin exhibition. That the principal lenders are national galleries reveals something of the history of Blake's work.

In his lifetime, Blake was widely dismissed as an eccentric mystic. Many of the illuminated volumes and pictures regarded as triumphs today remained unsold when he was alive or were commissioned by the small band of radicals, bibliophiles and artists, including George Cumberland and Henry Fuseli, who were Blake's patrons.

When the artist died in 1827, the bulk of his art belonged to his wife, Catherine, or to these supporters. But by the 1850s the British Museum had started its collection, and Blake's reputation underwent reassessment with Alexander Gilchrist's biography in 1863. Advocacy by the Rossetti brothers, Dante Gabriel and William Michael, boosted Blake's reputation further. By the beginning of the 20th century, as some of the patrons' families began to sell, interest was intense. When one of the greatest collections of Blake works came on to the open market, Charles Aitken, the director of the Tate (then the National Gallery of British Art) who had no purchasing budget, even put together a consortium to save it.

The collection comprised 102 illustrations for Dante's Divine Comedy which had been commissioned by another patron, John Linnell, in the latter years of the artist's life, and which remained with his family until the auction at Christie's in 1918. Aitken succeeded in his bid and the works were divided between the consortium members, which included the Ashmolean in Oxford, the Birmingham City Art Gallery and the National Gallery of Victoria in Melbourne, Australia. Twelve impressive watercolours are returning from Australia for this show. "It is ironic that in this movement from the private to the public, Blake, who saw himself as much a prophet as a poet or artist, is in the end achieving exactly what he hoped he would - that his message would live for future generations," Riding says.

Yet while most of Blake's work has moved into the public domain, there have always been private collectors. Geoffrey Keynes, brother of John Maynard, was among them, as was the painter and theatrical "angel", W Graham Robertson, who bequeathed his collection of Blake works to the Tate in 1939. One of the most important works, the so-called Varley sketchbook, has been lent for this exhibition by a collector who does not wish to be named. John Varley was another of Blake's acolytes, for whom the artist drew many of his dreams and visions, such as the famed Ghost of a Flea. Sir Peter Parker, the former head of British Rail, is another avid fan, collector and patron of the Blake society. A distinguished American scholar, Professor Robert Essick, has lent generously.

Christine Riding says she is not going to pretend that bringing together an exhibition on this scale is easy. "But it's a joy when the works start to turn up," she says. "People are realising this is the big Blake exhibition. It may never happen anywhere else, ever again."

* 'William Blake', supported by Glaxo Wellcome plc and 'The Independent on Sunday', is at Tate Britain, London SW1 (booking 0870 842 2233) from Thursday to 11 February.