His will was not activated until after his wife’s death almost 20 years later, in 1962, when the university was suddenly in possession of a sum of money previously never dreamed of. The bequest added up to some £2 million which, in today’s money, would be more than $43 million. And the terms of the will were both clear-sighted and pleasingly broad-ranging. The funds were to:

"make available to the people of Australia the latest ideas and theories in plastic arts by means of lectures and teaching and by the purchase of the most recent contemporary art of the world ... so as to bring the people of Australia in more direct touch with the latest art developments in other countries."

But, in the ensuing years, as the university grappled with the dilemma of how best to fulfil Power’s wishes, the man – the artist - behind the money was obscured. The funds were eventually used to establish the university’s art history department, the Power Institute of Fine Arts, in 1968. Part of the bequest also went towards setting up the Museum of Contemporary Art in 1989.

J.W. Power, in other words, had a profound effect on art history Australia. But he was also one of Australia’s most successful and accomplished inter-war modernist painters, with a relatively short but prolific career played out almost entirely in Europe. He lived and worked in France and England, and although he always identified as Australian, he arrived in London in 1906 and never returned. In the interim, he worked in the heart of the avant-garde movement in Paris, part of a prominent circle known as Abstraction-Création.

But he remained unknown as an artist in Australia, with a career that was neatly book-ended by the two world wars. The timing of his death, during World War II, ensured that his reputation as an artist would be all but lost in the cracks of history. Although his wife, Edith, bequeathed a large collection of his works to the University of Sydney, his own bequest served to overshadow him as a painter.

But a new exhibition at the National Library of Australia shines a light on Power and his work, bringing together for the first time his paintings from the University of Sydney and the dozens of sketchbooks held by the library in Canberra.

At the heart of the show is an almost exact recreation of an exhibition that would prove one of the high points of Power’s career, a solo show in 1934 in a Paris gallery run by Abstraction-Création. While few records of the show survived, two art historians from the University of Sydney, Ann Stephen and Andrew Donaldson, had already noticed numbers on the backs of some of Power’s paintings before they finally uncovered a detailed floor plan of the show among the artist’s papers. The university had all but two of the show’s 28 paintings, and was able to recreate, two years ago, the Paris show almost in its entirety.

The exhibition placed Power at the heart of a seminal and heady movement, in which art was being made, exhibited and discussed at length in Paris. But when shown alongside dozens of other works, and 30 of his sketchbooks, Donaldson says the Australian public will finally learn about Power the artist.

“We have the fullest possible account of Power that we’ll see,” he says. “The exhibition will tour later to the Heide Museum of Modern Art, but it’s an incredible opportunity at the National Library gallery to bring together work not just from the 1934 recreation, but work from the beginning, as it were, until the end.”

Born into a wealthy Sydney family in 1881, Power had always had an artistic bent; his mother encouraged him to draw and paint from a young age, and his grandfather was the prominent architect William Wardell, responsible for St Mary’s Cathedral in Sydney and St Patrick’s Cathedral in Melbourne.

Power studied medicine at Sydney University, graduated in 1905 and travelled to London to continue his medical studies in 1906, later serving as a medical officer in the British army during the First World War. It was shortly after the war ended that, perhaps undone by the horrors on the battlefield, he decided to give up medicine to focus on art.

He moved to Paris and studied under Fernand Léger at the Academie Moderne, a course that was fundamental in the development of the avant-garde movement between the wars. He kept a studio in Paris, and from 1925 was represented by Parisian gallery owner Léonce Rosenberg. His first solo exhibition was in London in 1927. But, says Donaldson, it was the publication of his book in 1932, Elements de la construction picturale, that marked his arrival in Paris.

“From that year onwards, he’s one of only a very few artists to participate in every exhibition of Abstraction-Création,” he says. “[The group] had everyone from Piet Mondrian to Jean Arp in it … because of course in the ‘30s, Paris became the last port of call as all these avant-garde artists were squeezed out by the rise of Fascism and totalitarianism.

“And in the middle of that huge, expatriate, cosmopolitan Paris, Power is having exhibitions within Abstraction-Création, he’s showing at the Galérie Jean Boucher, which is the finest avant-garde gallery in Paris in the '30s, and he has published this book and is known to everybody, and everybody knows him there. It’s just that that knowledge, that perspective, is not visible from an Australian art historical point of view.”

His sketchbooks, a lifelong habit begun during his early years in Sydney, give an even greater insight into Power’s development as an artist, from his early, Heidelberg-style sketches and watercolours, through to his Cubist and later abstract works.

“He’s part psychedelic surrealist, part biomorphic abstract - he’s a completely contemporary artist, in a way,” says Donaldson. “The sketches start in Australia - he’s got his eye on art before he’s even studying medicine, and while he’s studying.”

A multi-linguist, Power was able to mix seamlessly with the cosmopolitan set – the consummate expat in Paris.

“But he doesn’t return to Australia to announce his great achievements as the expatriates who do get incorporated in their accounts are. Instead, he dies during the war, having never returned, and that’s a recipe for invisibility.”

Ann Stephen, a senior curator at the University Art Gallery in Sydney, says Power’s book was, ironically, almost the only link he had to Australia, having left three decades earlier.

“He had left Sydney in 1906, and the only contact as far as we know was that when his book was published in the early '30s, he did send the Fisher Library here a copy, which said, ‘From an old student’, and that was it,” she says.

Power died of cancer in 1943, at the age of 62, in occupied Jersey in the Channel Islands. By the time his bequest finally made it to its intended recipient, almost two decades later, it must have seemed like a bolt out of the blue – a rich doctor, an Old Boy, about whom little was known.

But looking at his works today – rich with colour and strange combinations of form and concept – it’s hard to believe that his legacy was once so overshadowed. This was an artist who once complained, in a letter to a friend, that he could not keep up with the demands from his gallerist.

“We do know that he was exhibiting and selling and sought after,” says Stephen.

“It’s certainly true that Power didn’t need to sell his work, but on the other hand, artists don’t exhibit their work necessarily just to sell it; it’s very much about showing your work to your audience.”

Power’s collection of sketchbooks, along with other papers, came to the National Library as a donation from Edith Power’s niece, Ida Traill, in 1977. Among the papers were a collection of 10 pochoir prints by Pablo Picasso, all that remained of Power’s substantial personal art collection, which was sold after Edith died. Library curator Matthew Jones says the sketchbooks, kept by Power as a sort of visual diary, are as much an account of what Australians were doing in post-war Sydney as of Power’s career.

“Most of his work is sensuous and a bit playful, but some sketches are a bit disturbing, especially in the last sketchbooks he kept in his life,” he says.

The University of Sydney now has more than 1000 works by Power, including more than 150 canvasses. Seventy of these, including 26 from the 1934 Paris exhibition, will be included in the National Library exhibition, as well as 30 sketchbooks.

“I think what the National Library exhibition will do is really situate his early career, coming out of Australia, because we’re shown for the first time the Australian sketchbooks and also his years in the 1920s in Léger’s studio,” says Stephen.

He took his place not only among the avant-garde artists in Paris, but also the earlier English modernists. His later works, too, show a darker side to Power, as another war loomed.

It was a war that would spell the end of many things, including the life and career of one of Australia’s most successful ex-pats, whose memory was destined to live on, for a time, only in the annals of academia. With this exhibition, his life has been resurrected well beyond a mere footnote in Australia’s art history.

Abstraction-Création: J.W. Power in Europe 1921-1938 opens at the National Library on July 25 and runs until October 26.