His experimental investigative approach paralleled, and in many instances anticipated, the development of modern and contemporary art in New York and Europe including the work of Mark Rothko, Jackson Pollock, and Barnett Newman.

Burkhardt held his first solo exhibition in 1939 at Stendahl Gallery in Los Angeles, arranged by Lorser Feitelson, and, in response to the Spanish Civil War, he painted his first anti-war works.

From the late 1930s he began to produce apocalyptic anti-war compositions, a theme which became particularly pronounced in an abstract expressionist style after the atom bomb was dropped on Hiroshima and Nagasaki at the end of the Second World War.

[7] In the 1970s Burkhardt continued his anti-war paintings—incorporating protruding wooden spikes into the canvas—while simultaneously painting abstractions of merging lovers and cityscapes during his summer visits to Basel.

In 1993, the last year of his career, his final series “Black Rain” channeled pain and hardship, but provided poignant, symbolic beacons of hope and wishes for a better future for humanity.