David Mellor’s interest in the Bloomsbury Group dates back to his days as a student, when he was taught art history by Vanessa Bell’s son Quentin.

“One day Bell asked if we wanted to have tea with Duncan Grant at Charleston [the Sussex farmhouse near Firle which provided a base for Grant and Bell],” he says as he prepares for last weekend’s opening of the Radical Bloomsbury exhibition.

“Grant was extraordinary. He was in his early 80s at that point, but he was incredibly funny and witty.

“He had always been very personable – Matisse and Picasso had liked this spry little Scottish guy who was always laughing.”

Radical Bloomsbury reveals a pair of artists working on the cutting edge of the British art world, taking influences from the new art movements taking over Europe, and their own travels.

But that sense of humour can also be seen in some of the pictures – such as Grant’s comical take on ancient classicism in some of his early works and his idiosyncratic version of a Biblical tale in the Queen Of Sheba.

Look deeper into the Bloomsbury Group’s history and a clear picture of friends who enjoyed a life of dressing up and fun emerges, a contrast to the darker shadow often cast over the group largely caused by the 1941 suicide of Vanessa Bell’s sister, the novelist Virginia Woolf.

Within the summer exhibition are pictures from trips to France, Italy and Grant’s early life in India, playful portraits of close friends, such as the mountaineer George Mallory, and relatives in flamboyant Byzantine and Russian costumes, photographs from their private family albums and even an image from the infamous Dreadnought Hoax, in 1910.

The notorious hoax saw Grant, Woolf and Bell’s brother Adrian Stephen gain access to the new battleship HMS Dreadnought in Portland Harbour by dressing up as members of Abyssinian royalty, and caused a scandal about the dockyard security.

This underlying sense of fun is just one of the revelations in this new exhibition, which has seen works from arguably Bell and Grant’s most creative and experimental period gathered together from collections across the world.

The exhibition has been divided into six roughly chronological themes.

It opens with Bloomsbury Before Bloomsbury, covering the pair’s development as artists – including a photograph of Bell at work on her first displayed portrait, and a pen-and-ink drawing by a very young Grant.

Further on, the exhibition explores their interest in the exotic and oriental, their encounters with modernism, English expressionism and abstract work; and finally their post-First World War return to hearth and home.

“We focused on the period from 1905 when they were beginning to express themselves as artists to 1925,” says keeper of exhibitions Nicola Coleby.

“We wanted to look at the period when they were interacting both with other artists and what was going on in France with the Post-Impressionists. Their strongest work was in those two decades – they were at their most experimental before 1920.

“After 1925 they had developed their own language and didn’t tie in with the avant garde so much. They were still so prolific – there is a huge quantity of work. We chose quite carefully to pick some of their strongest pieces.”

Although the original idea was to include work by other Bloomsbury artists, such as Roger Fry or Dora Carrington, the decision was made to focus the exhibition on Grant and Bell to use the space to its best advantage.

“They weren’t solely responsible for the revolutions in British art in the early 20th century,” says Coleby. “But I think they were perhaps some of the first to look at Cezanne and Picasso and use their work in their paintings. They in turn influenced other British artists.”

It was the Bloomsbury Group, most specifically Roger Fry and Clive Bell, which was behind the two exhibitions of Post-Impressionists in London in 1910 and 1912. These featured paintings by Paul Cezanne, Paul Gauguin, Vincent Van Gogh, Henri Matisse and Pablo Picasso, as advertised on a poster for one of the shows drawn by Grant, showing how close he was to their organisation.

These two exhibitions are frequently named as the birthplace of modernism in the UK, inspiring a whole generation of artists and writers by bringing in artistic movements including fauvism, expressionism, cubism and divisionism.

Examples of these different movements can be seen throughout Bell and Grant’s paintings featured in the exhibition, including some of their most famous works.

Bell’s The Tub takes inspiration from Matisse in terms of its background and colour, and Grant’s The Ass features Picasso-like hatching. There are plenty of examples of divisionist “dot-style” painting in Grant’s work – particularly the Queen Of Sheba.

Their work went on to influence others. Mellor points to the curved female figure at the centre of Venus And Adonis by Duncan Grant, in the final gallery of the exhibition. It bears close resemblance to Henry Moore’s future sculptures – something Mellor puts down to the fact the painting used to hang in the faculty of arts at Leeds where Moore studied.

Born in 1879 to Sir Leslie and Julia Stephen – themselves regular hosts of literary salons, and whose photos feature in the exhibition – Vanessa Bell married the art critic Clive Bell in 1907.

Her early work Iceland Poppies, a highly symbolic still life featuring not only the titular flowers but also a funeral urn and bottle of poison, is one of the first pictures in the display and shows her early adventures in the international avant garde of Symbolism.

By 1916 Vanessa had moved with her two children to Charleston to live with Duncan Grant and his gay lover David Garnett. Grant is believed to have fathered her daughter Angelica, who later went on to marry Garnett.

Grant, who was born in 1885, was the son of a Scottish Army officer – ironic considering the Bloomsbury Group’s status as conscientious objectors.

He spent the first nine years of his life in India, and studied in Paris, before moving to London’s Fitzroy Square in 1909 where he became a regular at Virginia Woolf and Adrian Stephen’s Thursday night gatherings – the original home of the Bloomsbury Group.

Grant’s early Eastern influences can be seen in the second part of the exhibition – not least in the large 1911 painting Bathing, which dominates the room. The waves splashed through by the swimmers resemble the shapes seen in Byzantine mosaics.

Grant was also the co-director of the experimental Omega Workshops with Roger Fry in 1913, which produced some of his and Bell’s most abstract work – an experimental side to the Bloomsbury Group artists which is not as well known.

Among the amazing exhibits on show are Bell’s paper collage portrait of long-time sitter Molly McCarthy, created sometime between 1914 and 1915 in a clear nod to Cubism. There are also examples of her abstract textile work on show.

But possibly the most unusual piece is Duncan Grant’s Abstract Kinetic Painting With Sound. Created in the same time period as Bell’s Portrait Of Molly MacCarthy, the piece is a long non-representational scroll painting, which was originally intended to be seen passing through a mechanism so that the blocks of colour moved and danced to the sounds of J S Bach’s Brandenburg Concertos. Alongside the original scroll is a sketch of the machine Grant envisaged to display the work, and a video recreation of it soundtracked by the classical music.

These experiments contrast sharply with the direction the pair went into following the “war to end all wars”, when both Bell and Grant focused back to the home and figurative work – probably the period visitors to Charleston are most familiar with.

“Following the war there seems to have been a move away from artists’ interest in the machine age,” says Coleby. “There seems to have been more value placed on the domestic, and more conservative subjects.”

Among the paintings in this final section of the exhibition are views from Virginia Woolf’s Rodmell home Monk’s House, and domestic still lifes.

Probably most revealing is Bell’s The Kitchen, which depicts the unorthodox space Bell and Grant shared at Charleston. A whirl of activity moves around a stationary mother and child in the foreground.

There are also examples of the decoration Bell and Grant gave to their living space, with a painted corner cupboard and kitchen cupboard doors both on display – familiar sights to anyone who has been to Charleston, but two pieces that won’t have been seen by most visitors.

The exhibition closes with a series of portraits of close friends and family, including an unsympathetic picture of Clive Bell’s mistress Mary Hutchinson, and beautiful paintings of Virginia Woolf knitting in Asham House, near Newhaven, and Bell herself painted at Charleston.

It was the tight-knit nature of the Bloomsbury Group which may have led them to fall out of favour in the middle of the 20th century.

“As a group, Bloomsbury could be very independent,” says Mellor. “They didn’t need anybody to give them a leg-up, they constituted a new establishment.

“They were their own micro-society, which could be very welcoming but at the same time it could exclude people. A lot of people either love or hate their work.”

It was in the early 1960s that their work began to be reassessed again, partly because of Quentin Bell’s influence, although Mellor confesses the Bloomsbury artists are probably more appreciated in Europe and the US.

That said, among the group’s fans are Roxy Music frontman Bryan Ferry, who has lent works to the exhibition including Vanessa Bell’s Summer Camp.

“They really set the pace for innovation with works like Abstract Kinetic Painting With Sound, the interest they had in Eastern cultures, and their significant place in how Modernism developed in the 1920s,” says Mellor.

“I have curated exhibitions since the 1970s to do with people like Francis Bacon, and a lot of photography and pop art displays.

For me this exhibition is a revisitation of my past, and where it all started.”

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