The challenge when hanging new art exhibitions is often not about choosing what to show but where to find it.

To ensure a John Piper retrospective opening at Eastbourne’s Towner Gallery this week features some never-before-seen gems, curator Nathaniel Hepburn used his usual creative tenacity.

He once located a rare painting for another exhibition after spotting it hanging in the background of a photograph in a supermarket magazine.

Putting together his latest project, filled with works by the 20th-century artist John Piper made in Kent and Sussex, he had another piece of serendipity.

One of Piper’s Romney Marsh paintings, Ivychurch from 1947, was bought by its current owner after its first exhibition.

And, like many of the show’s rarities, it had not been seen since.

“I was having dinner with somebody who mentioned he had been on holiday to the Hebrides and thought he had seen a picture very similar to that hanging above the mantelpiece.

“He said next time he visited he would have a closer look and a few months later I received a phone call from a remote Scottish island saying ‘I’ve got a John Piper hanging above my mantelpiece’.

“It’s the first time it will be exhibited for 50 years, would you like it for your exhibition?’”

Hepburn snapped his hand off.

The moody painting, done in the fallout of the Second World War, features a sturdy stone church set among dark, stormcloud-filled skies.

“Those late 1940s works are what many people would recognise as Piper’s mark,” says Hepburn.

“There is a moodiness about them which led King George to say, as he leafed through the views of Windsor Castle, ‘You haven’t had much luck with the weather, have you, Mr Piper’.”

Ivychurch is one of 120 pieces in the show Hepburn found with the help of two generations of the Piper family.

It is fitting that the works have travelled from private collections and galleries from the tip of Scotland to the Channel Islands.

Piper loved to travel. He received a copy of Highways And Byways for his tenth birthday and from then on a different guide every birthday. He used to pack these into his satchel as he biked around the Sussex lanes to make the early oils and sketchbook studies that would later be used during his editorship at the Shell Guides.

Most retrospectives are arranged chronologically. But because geography and a sense of place are so important to Piper’s work, Hepburn chose to organise the show around Kent and Sussex.

It is unusual but appropriate. The two locations crop up throughout Piper’s life. He repeatedly painted the varied landscapes that attracted him to Sussex: Brighton’s Regency architecture, the ramshackle coastal quirks (the flags and boats and harbour at Newhaven), the Seven Sisters’ cliffs. In Kent, favourites were the Dungeness coast and Romney’s churches.

His other great inspiration at the time was French cubist Georges Braque. He lived in Dieppe, just across the channel.

“I don’t know whether he ever met Braque but he was heavily influenced by his collages and paintings in the 1930s,” says Hepburn.

“But Kent and Sussex were important throughout his life and the exhibition traces his passion for them all the way through, from aged 17 to his 80s.”

It was here in the 1930s he had a real period of experimentation.

“He was trying to find what type of artist he was going to be.”

Born in Epsom, Surrey, in 1903, Piper (against his father’s wishes that his son become a lawyer) left for London’s Royal College Of Art. He managed only a year before deciding to move to a cottage in the Surrey countryside with his new wife, an acquaintance from art school, while keeping a flat in the city.

He began to visit the South Coast.

“One of the works is Rose Cottage at Rye Harbour which Piper painted in the 1930s. He used to rent the cottage. It is quite telling of Piper’s love for the Sussex coast this picture stayed in his possession until his death in 1992.”

Enter the exhibition’s early rooms and those different styles of collage, painting and experimentation with abstract art from Kent and Sussex greet you.

“It is important because it shows Piper finding his style,” believes Hepburn.

“It is also an area that will surprise people who think they know Piper’s work as wartime paintings, views of stately homes or the Windsor Castle picture he painted for the Queen Mother.

“For the people who know that side of his work, the 1930s will be a real discovery.”

Piper’s strength was his versatility, his range of skills and techniques and media. He made tapestries, stained glass, ceramics, decorated furniture.

At the Shell Guides, where his friendship with the poet John Betjeman blossomed, he revealed formidable editing and photography skills.

Ironically, though, it was the versatility, combined with the move from abstract art to what was then perceived as a more conventional style, topographical landscapes, which pushed him from favour.

But, as Hepburn explains, “It is through exhibitions like this we rediscover the energy, the joy, the relevance of those later works.”

Benjamin Britten was another important friend who shaped Piper’s evolution. Both understood the value of collaboration, why an artist must recognise his surroundings.

They worked together on many operas including three at Glyndebourne. Piper designed the costumes and sets. Britten did the music.

“By all accounts Britten was not the easiest person to work with but the two had a friendship that lasted for many years. Britten and his partner Peter Pears built a great collection of Piper’s work.”

Through his friendship with Britten, seeing his collection of 18th-century aquatints, and also Jim Richards, then editor of Architectural Review, Piper began to depict architecture, best highlighted by the Brighton Aquatint series, a style which was considered antiquated at the time.

“There are some lovely scenes with humour and liveliness which capture what Brighton feels like. The Metropole Hotel with rain cut into the etching right across the image. A view called Mixed-style Regency Modern, featuring Embassy Court and the Regency terraces, with the juxtapositions he loved which are still in Brighton now.”

The show’s bounty, Dead Resort, Kemptown, is from that period.

In 1939, maturing, Piper left behind the coastal gaiety and abstraction to bring together his love of architecture and sense of place in one picture.

“There is the abstraction, the architectural details and flourishes, and it feels like a stage set that inspired his work for Glyndebourne later,” concludes Hepburn.

“It really sums up many elements of his work and what makes him so interesting and unique.”

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