He was married four times, and bore a son, Ulrich, from his first marriage. He lived illegally in Paris for several years during the 1920s and 30s. He was a founder member of the Cologne Dada group. He was highly experimental in his artworks, and pioneered a number of techniques, including frottage, which uses pencil rubbings of objects as a source of images, and grattage, in which paint is scraped across canvas to reveal the imprints of the objects placed beneath. Collages, which he first produced in 1919, came to dominate his artistic pursuits in later years.
In 1938 Ernst was interned in France, but discharged a few weeks later. During the Nazi occupation of France, he was arrested by the Gestapo, but escaped and fled to America with the help of Peggy Guggenheim, a patron of his art. Ernst and Guggenheim arrived in the United States in 1941, were married in 1942, and divorced in 1946. In the same year he married Dorothea Tanning. In 1948 he wrote the treatise Beyond Painting, which earned him financial success. In 1953 he and Tanning moved to France. He died in Paris in 1976.