Koppel contributed to a "flowering of the arts" in the Welsh valleys
A Jewish refugee's paintings of postwar life in the south Wales valleys have gone on display in Berlin.
Artist Heinz Koppel fled Germany with his family following the rise of the Nazis, settling in Dowlais near Merthyr Tydfil.
Many of his works can be seen in museums and art galleries in south Wales, but he remains relatively unknown in his native Germany.
The exhibition at the Centrum Judaicum in Berlin continues until January 2010.
Heinz Koppel: Ein Künstler zwischen Berlin und Wales (an artist between Berlin and Wales) celebrates Koppel's work 90 years after his birth as an example of the many Jewish émigrés who had a major impact on the British arts scene during and after World War II.
Born in Berlin in 1919, Koppel took up art as a youngster and continued his studies through turbulent times for Jews in Germany.
The Koppel family first fled to Prague in 1933 and then London in 1938, but Heinz's mother Paula was unable to join them.
Debilitated by bouts of arthritis, she stayed on in Prague and was sent to her death at the Treblinka concentration camp.
Heinz's father Joachim set up a zip factory on the Treforest Industrial Estate near Pontypridd, while Heinz remained at art school in London until 1944.
Influenced by the German expressionist school and early mentors such as Grigorij Oscheroff and Friedrich Feigl, Koppel's art developed further in his new homeland under the tutelage of fellow émigré Martin Bloch, together with his own growing interest in Freudian psychoanalysis.
The exhibition was conceived by Chana Schuetz, art historian of the Centrum Judaicum Foundation, along with its director Hermann Simon. In the foreword to the exhibitions catalogue, they describe Koppel as "a forgotten painter; none of the desired critical appraisal of his life's work has been forthcoming until this exhibition ... Koppel's paintings - often the expression of his own psychological turmoil - pose riddles and invite closer study."
Anna Canby Monk of the Centrum Judaicum's exhibitions office says Koppel came to south Wales at a time when a minor flowering of the arts was taking place in the valleys.
"Artists were finding rich and substantial subject matter in the run-down industrial towns and their inhabitants," she says.
"Koppel had more access than most to the lives of these working class families: he taught painting to adults and children in Dowlais.
"But because teaching is essentially transaction, not merely imparting, he learned from his students during this time too."
Koppel left south Wales with his wife and children in 1956, teaching and painting in London and Liverpool before settling in Llety Caws, a rural farmhouse in Cwmerfyn near Aberystwyth.
He continued to paint until his sudden death in 1980 aged 61.
Ms Monk said it was right that Koppel should be recognised as a great artist in his native Germany, even if he had to go elsewhere to pursue his talent.
"Just as Koppel's work was a boon to the postwar British art scene, here in Berlin one must recognise the great loss to the artistic life of the country that was brought about by his and other young artists' exodus."