Louis le Brocquy: Painter thought by many to be Ireland's greatest of the 20th century

Louis le Brocquy, who has died aged 95, was among the greatest painters produced and nurtured by Ireland. While determinedly positioning himself in the European mainstream, Le Brocquy was first and last an Irishman who found his artistic roots not only in those he called "my masters" – Velazquez, Goya, Manet and Cézanne – but also in Jack Yeats, Irish travellers and the dark age tales of Cú Chúlainn.

For his 90th birthday, Le Brocquy was honoured with exhibitions in London and Paris, and in Dublin, Cork and Limerick, a cross-section of cities that maps his cultural landscape. In one of these, Gimpel Fils in London, he paid homage to his masters with four large "Odalisques", luscious reclining nudes inspired by Goya and Manet. The show was demonstrative of Le Brocquy's lifelong approach to his work: elegant, articulate, purposeful, and presented in the full knowledge that he was but part of a long cultural tradition reaching across nations and peoples.

Louis le Brocquy was born in Dublin in 1916, the eldest of the three children of Albert le Brocquy, the secretary to his family firm the Greenmount Oil Company, and his wife Sybil, née de Lacy Staunton. Louis' paternal grandfather was a Belgian oil-refiner who settled in Dublin in the 1880s; his mother was later one of the founders of Amnesty International in Ireland, and a driving force in the 1960s behind the saving of Dublin's Gate Theatre.

Le Brocquy studied chemistry for two years at Trinity College, Dublin, but found himself more interested in the colours of chemistry than in its commercial applications. The fundamental colours of life, he observed, were red haemoglobin in blood and green chlorophyll in plants. Red, a primary colour, and green, the product of the two other primaries, look so alluring together because, as he put it, "they are each what the other longs for, the final ingredient required to make white light."

As a young man he studied art by looking at old masters, both in reproduction and at the National Gallery of Ireland. His early ambition to become "a good painter... to join in the spiritual excitement of a great creative tradition," led him away from chemistry and towards painting. He did not go to art college, and as a result was dogged by the phrase "self-taught", which suggests a kind of naive innocent determination. This was not Le Brocquy's property at all: his scientific background gave him a fresh perspective that few artists of his generation were lucky enough to share. Empathy for science and scientists was the live current flowing through Le Brocquy's life and work from the beginning.

Louis le Brocquy was tall and trim, and though he carried a stick and wore a jaunty hat, he was never a dandy. The quiet Irish lilt in his voice, the way he inclined his head to listen, and his soft inquisitive eyes, encouraged anybody so inclined to come and talk to him. Walking round the Dublin galleries with Louis was an experience to treasure – not only for his observations, nor for the picturesque unfolding of his lean, articulated self from taxis, but also for his courteous and generous responses to the surprise of gallery-goers as he materialised in front of one of his own paintings. In Dublin, men and women would stop him in town, shake his hand and ask to have their photograph taken with him; the poetic roots of Ireland, of Joyce, of WB Yeats, of Le Brocquy, are still detectible there at street level.

In Dublin in 1938 Le Brocquy and Jean Stoney, a surgeon's daughter, met and later married in London. A daughter, Seyre, was born the following year. Despite gathering international tension, the couple travelled in France, Switzerland and Italy before returning to Dublin in 1940. By 1941, however, they had parted and Louis moved to London. His paintings in this period reflect the formidable presences of fellow Irishman William Orpen, and while Le Brocquy now painted firmly proportioned and constructed figure groups, he was gradually allowing white to begin to flood his palette. White followed Le Brocquy around all his life: from the white of the bandage over his eyes when he banged his head as a boy; the white of the snow drift he was caught in while skiing in Switzerland; and the white of the marriage of red and green.

The travelling people of Connemara, whose insistence on freedom was likened by le Brocquy to the independence of the artist, were the subject of the first exhibition Le Brocquy held, in 1947 at Gimpel Fils. This was the beginning of a 60-year association with the gallery, and the year in which Eduardo Paolozzi, Prunella Clough, Patrick Heron and Lucian Freud also made their London debuts.

But Le Brocquy did not join any set or group of artists. Instead he found companionship in the art communities available to all, the museums and galleries of Dublin, London, Paris and Madrid where he studied the old masters, his masters. That said, friendships with fellow artists ran ineradicably through his life. In 1947 he became a visiting instructor in painting and mural design at the Central School of Arts and Crafts, where he made new friends in Mervyn Peake, Paolozzi, Heron and Francis Bacon. Seven years later he became visiting tutor in textile design at the Royal College of Art.

Visiting Spain in 1955 he found himself in a village in La Mancha where in brilliant sunshine he came across a group of women and children standing against a whitewashed wall. "The sheer brilliance of the sun had absorbed these human beings into invisibility," he wrote. "Only their shadows remained, deep as night. I had witnessed the light as a matrix from which the human presence had emerged and into which it could, ambivalently, disappear." This was a revelatory experience which gave birth to the seminal "Presence" series of paintings in which the human figure is reduced to a torso, with the spine as a prominent vertical. With their stark whiteness, and pin-pricks or knife cuts of sharp colour, these works came to characterise le Brocquy's art.

Le Brocquy found his soulmate, the painter Anne Madden, at a party in London in 1956, the year he represented Ireland at the Venice Biennale. Anne mistook him for a guards officer until she was introduced to this handsome 40-year-old artist with silver-gilt hair. Within days they were at the Royal College fancy dress ball, within a year they were sharing a studio in Kensington Gore, and within two years they were married.

Young Woman (Anne), one of the most important of the "Presence" paintings, was made in 1957 during a series of surgical operations that Anne had to undergo as a result of a riding accident in her teens that had damaged her spine. For months afterwards she lay on her back in a white-plaster sarcophagus made from a cast of her body. The red slash on the spinal column of Young Woman (Anne) evokes the "terrible anatomical carpentry" that she suffered, and the X at her upper legs draws the idea that both sides of the body are being examined by the artist. "I am an internalised painter," Le Brocquy reflected to me in July 2006.

Anne and Louis moved to France after their marriage to a dilapidated mill in Provence, and in 1960 to a villa in the Alpes Maritimes. There they built a studio and brought up their sons, Alexis and Pierre. Their migration – planned to give Anne the warmth she needed for recovery – also enabled them both to be identified even more securely as European artists. They worked together, one at each end of the long, light studio, each able to give the other, as Anne put it, "stringent criticism of a creative kind". Anne recalled that Bacon "often reiterated our luck in this respect. He himself 'longed' for such an other." At Carros they put their roots into the local community and lived a Virgilian life among vineyards, mimosas and orange groves. The smell of drying paint might, in the winter, be mixed with the sticky steam from marmalade making; in the summer the swimming pool would boil with excited children; in the autumn the smell of figs soaking in grape juice would fill the studio. Idyllic, perhaps, but always their lives infected their art.

Le Brocquy destroyed a large number of paintings in 1963, during a period of despair. As Anne put it, "that blight most dreaded by artists had crept into him – the loss of inspiration... He had painted himself to a standstill." In chucking out the old to make room for the new, Louis came to understand, in conversation with his friend, the artist Joan Mitchell, that the paintings he had destroyed had in fact been painted by "Henry, the monkey which lurks in us all."

At Anne's suggestion, she and Louis went to Paris, where, at the Musée de l'Homme, Louis discovered the Polynesian head cult: skulls overlaid in clay and painted to preserve the presence within. Inspired by these, and another ancient head cult in the French Midi, Le Brocquy developed a series of anonymous "Ancestral Heads." These were followed through the mid 1970s by the many "Head Images" of artists whom Le Brocquy regarded as "exceptional instances of human consciousness", including WB Yeats, whom he had known in the 1930s, Joyce, Lorca, Picasso, and his friends Bacon and Samuel Beckett. The "Head Images" are not portraits: Le Brocquy said that he was not making a statement, but trying to discover aspects of the Beckettness of Beckett, the Baconness of Bacon.

Le Brocquy also found inspiration in still life, flowers and in the Irish landscape. The watercolours of Ireland create yet another distinct group of works in which the identity and essence of the country floods on to the paper. Water is both the medium and the subject; colour goes where it will within the invisible boundaries laid by this master magician. They are distillations of a lifetime's experience, the discoveries of an astonished traveller on returning home.

In 1996 Louis and Anne left France and settled not far from the centre of Dublin in a deceptively small terraced house which opens into wide, white spaces, an attic studio and an exotic hidden water garden. Here Le Brocquy further developed his "Presence" paintings into the series of "Human Images", in which isolated features – ear, mouth, navel – emerge from a void alone on the canvas. With these works le Brocquy perfected the use of thin attenuated glazes laid all over the canvas, brilliant red, blue, viridian green, thinned to homeopathic quantities with white spirit.

Into his ninth decade Louis le Brocquy continued to explore, discover and learn: "I believe I have gradually learned from these last paintings something of the paradox that – although the essential and ultimate state of the human individual is aloneness – each one of us remains part of our physical, metaphysical, social and cultural environment, 'breathing', as it were, inhaling and exhaling, absorbing and reaching outward within its complexity."

Dexterity was not, he insisted, what he was looking for.

James Hamilton

Louis le Brocquy, artist: born Dublin 10 November 1916; married 1939 Jean Stoney (divorced 1948; one daughter), 1958 Anne Madden Simpson (two sons); died Dublin 25 April 2012.