Ernst Fuchs was born on February 13, 1930 in Vienna, Austria. His father, Maximilian Fuchs, son of an orthodox Jewish family, had turned down a career as a Rabbi, leaving his theological studies uncompleted. He married Leopoldine, a Christian. When the Nazis occupied Austria in March 1938, Maximilian Fuchs emigrated to Shanghai. Ernst remained in Vienna together with his mother, but Nazi legislation made it illegal for Leopoldine to raise her son. Ernst was deported to a transit camp for children of mixed racial origin. Thereupon Leopoldine Fuchs agrees to a formal divorce from her husband, thus saving her son from the extermination camp.

In 1942 Fuchs was baptised as a Catholic, an event of the utmost significance for him that determined his future life and work. He feels the calling to become an artist and began taking lessons in drawing, sculpting and painting with Alois Schiemann, a well-known painter and restorer. He subsequently received tuition from Professor Fröhlich and the sculptress Emmy Steinböck. He went on to study with Professor Albert Paris von Gütersloh at the Vienna Academy of Art. There he encountered the work of Egon Schiele and Gustav Klimt. In 1948 he was instrumental in the founding of the "Vienna School of Fantastic Realism" together with Arik Brauer, Wolfgang Hutter, Rudolph Hausner and Anton Lehmden. He participated in the first exhibition of the Vienna Art Club in Turin/Italy.

Ernst Fuchs settled in Paris where he remained for 12 years. After many years of misery and poverty he eventually began to receive international recognition. Between 1952 and1956 he traveled to England, Spain, Italy and an 18-month stay in the USA. In 1956 Fuchs moved to Israel where he lived in the Dormition Monastery on Mount Zion and painted Icons. He devoted all his energies to furthering Jewish-Christian understanding and to working as a church painter. Fuchs was commissioned to paint the Drei Mysterien des heiligen Rosenkranzes (Three Mysteries of the Sacred Rosary) for a newly-built church in Vienna. His paintings caused a storm of protest. Some of his most vehement detractors demanded that the pictures be removed from the church.

In 1974 he returned to Austria where he acquired the Otto Wagner villa in Vienna-Hütteldorf. He began to work for cinema and stage, designing stage sets for the opera houses in Hamburg for "Parsifal" and "Magic Flute", in Munich for "Lohengrin" and in Vienna the "Tales of Hoffmann" and "Josephslegende." Simultaneously he worked on a series of water-colour paintings of Lohengrin - and on his philosophical essays and poems. In 1988 he opened the Ernst Fuchs Private Museum, on the occasion of the centenary of the "Villa Wagner". As a printmaker he produced several important cycles of prints, such as Unicorn (1950–52), Samson (1960–64), Esther (1964-7) and Sphinx (1966-7; all illustrated in Weis). The artist lived and worked in the south of France. He continued to work in many media until his death in Vienna on November 9, 2105. He was married three times. In 2012 Fuchs became engaged to the singer Uta Saabel, his most recent muse. He is survived by 16 children.