Herb Aach was recognized by the New York art scene of the 1960s-80s for his individual and unique use of color. Born in Cologne, Germany in 1923, Aach studied painting as a young boy with expressionist Ludwig Meidner (1884-1966), for whom he also served as atelier boy, until Nazi persecution forced his immediate family to flee to New York, where he arrived in 1938. He enlisted in the U.S. Army in 1942 and became a United States citizen in 1943. The Army sent him back to Europe where he later served in Military Government in Kassel, Germany. Upon his return to New York in 1946, he resumed his art studies at The Brooklyn Museum Art School with John Ferren and Rufino Tamayo. He would always consider himself an American painter. In 1948, after marrying, he moved to Mexico for two years to study art at the Escuela de Pintura y Escultura in Mexico City.
It was in this period that, in part due to the influence of John Ferren, Aach acquired the strong preoccupation with color that shaped the rest of his career. For nearly 10 years, between 1954 and 1963, he experimented with and consolidated his thinking about color, developing a style he called color expressionism in the relative isolation of Hazleton, PA, where while formulating paints for the Art Crayon Company, he gained access to otherwise unobtainable pigments. A note on the back of one painting from this period reads "This is most likely the first painting to use the new Monastral reds, yellow, and blue shades, developed by Dupont. Pigments were lab samples prior to plant production given to me and began use on April 30, 1958." He made his own paints and packed them with pigment, and by the mid 1960s, because of their intensity and inner light, he turned to fluorescent pigments.