Corneille: Artist who helped set up the CoBrA group which placed spontaneity ahead of theory

In November 1948 six artists walked out in protest from a conference on surrealism being held in Paris. They resolved to form a new group, which they named CoBrA, after the initials of Copenhagen, Brussels and Amsterdam, the home cities of its founders: Asger Jorn, Joseph Noiret, Christian Dotremont, Constant Nieuwenhuys, Karel Appel – and Corneille, who was the last surviving Dutch member of this original core.

Their manifesto, La Cause Était Entendue [The case was heard], written by the former surrealist Dotre-mont, eschewed what they saw as surrealism's overly theoretical approach. Instead, they advocated spontaneity and complete freedom of expression, undertaking to "...maintain international activity... through experimental and organic collaboration, which avoids sterile theory and dogmatism." Corneille later explained, "We used everything and loved everything. We took from children's drawings, folklore, drawings by the insane, negro masks...". The short-lived CoBrA group would go on to change the face of Dutch and Scandinavian art, bringing a welcome renaissance after the gloom of wartime.

Corneille was born Guillaume Cornelis van Beverloo in 1922 to Dutch parents who had emigrated to Liège from Rotterdam. While primarily a self-taught painter he also studied briefly at the Academy of Art in Amsterdam but found the environment too conservative and stifling. He drew inspiration from the works of Paul Klee and Joan Miro, especially in their use of colour and form.

Corneille's first solo exhibition was held in Groningen in 1946. A year later he joined up with his friend Karel Appel for a show at 't Gildehuys in Amsterdam. CoBrA's debut group exhibition was held at the Stedelijk Museum in 1949 and attracted controversy, critics variously describing it in terms such as "Madness elevated to Art" and "Scratching, Blathering and Daubing". That same year Corneille illustrated Dotremont's Promenade au pays des pommes, a beautifully-produced book in an edition of 12 copies.

In 1950 Corneille moved to Paris, his base for the next 60 years. The second – and final – major CoBrA exhibition took place at the Palais des Beaux-Arts in Liège in 1951, showing works by the group, which by now numbered 17 members. In addition to his painting and drawing, Corneille had been a frequent contributor of poetry to the 10 editions of CoBrA magazine published up until 1951. Internal disagreements led to the group disbanding that year, although many members remained in contact as friends and colleagues.

During the 1950s and '60s Corneille travelled widely and collected African art and sculpture, which was to provide a further influence on his work. While his earlier paintings tended to use muted colours and were semi-abstract or presented indistinct figures, in 1963 he started to paint using a table top as his "easel". This horizontal plane gave him easy access to all parts of the canvas and allowed him to work on a larger scale, with themes including animals in nature and nudes, using bright primary colours.

Throughout his artistic life he had been involved with printmaking. A suite of his lithographs, For Jorn (1975-76), is in the Tate collection. In 1988 he assisted with the making of the film by Jan Vrijman, CoBrA, een opstand tegen de orde ("CoBrA, a revolt against the order"). That year also saw the publication of a monograph by Marcel Paquet titled Corneille ou la sensualité de sensible ("Corneille or the sensuality of the sensitive"). In 1997 he was made a commander in the Orde van de Nederlandse Leeuw [Order of the Netherlands Lion], one of the country's highest honours.

Corneille had been involved in supporting the activities of the CoBrA museum in Amstelveen since its foundation in 1995. The exhibition CoBrA Museum: 15 Years! opens in October and will include some of his work. "He was the best 'ambassador' for the CoBrA art movement," Lieke Fijen of the CoBrA Museum said of him. "In his special way he made it very clear and explained wonderfully, as an initiator and witness, why CoBrA was so very important, especially for modern art in the Netherlands. For the CoBrA Museum it always was a great pleasure and enormous honour to work with him... Now CoBrA definitively belongs to history."

Guillaume Cornelis van Beverloo (Corneille), artist: born Liège, Belgium 3 July 1922; married Natacha (one son); died Auvers-sur-Oise, France 5 September 2010.