Conrad Marca-Relli was born to Italian parents in Boston on June 5, 1913. In 1927 he moved to New York with his family. He attended a private art school and took evening classes in painting, developing an interest in Italian Renaissance art. In 1930 he enrolled in an art program at the Cooper Union Institute, New York. While working at the WPA Federal Art Project from 1935 to 1938, he got to know such artists as Willem de Kooning, John Graham, and Franz Kline, who led him to completely change his vision of painting.

After completing military service, Marca-Relli moved to Birdcliff, near Woodstock, where he produced paintings that were clearly influenced by Surrealist and Metaphysical art. Back in New York in 1947, he held his first solo exhibition at the Niveau Gallery and went to Paris in September of the same year. In 1948, disappointed by the Parisian art scene, he moved to Rome, where he exhibited for two consecutive years, joined Italian artistic circles, and befriended Afro Basaldella. His paintings from this period are characterized by increasing abstraction. In 1949 he went back to the United States and founded the Eight Street Club with de Kooning, Kline, and Mark Rothko. In 1951 he promoted the Ninth Street Show, a self-organized group exhibition of Abstract Expressionist art. In 1953 he organized the second Ninth Street Show at the Stable Gallery, where he also exhibited his first collages. The same year he moved to East Hampton, Long Island, and become close friends with Jackson Pollock.

In the 1950s and 1960s the artist gained increasing recognition. He won the Chicago Art Institute’s Logan Medal in 1954, showed at the Venice Biennale in 1955, participated in the Documenta II, Kassel, in 1959, exhibited with Robert Motherwell in Düsseldorf in 1961, and took part in Abstrakte Americanische, an important Abstract Expressionist exhibition in Darmstadt the following year. The Whitney Museum of American Art, New York, presented a retrospective of his work in 1967. Throughout the 1970s and 1980s he spent time in Italy, New York, and various European capitals and lived on a boat in France and the Balearic Islands. He moved to Parma in 1997 and the following year exhibited at the Peggy Guggenheim Collection in Venice. Conrad Marca-Relli died in Parma on August 29, 2000. That same year the Darmstadt Mathildenhöhe Institute presented a career retrospective of his work.