George L. K. Morris, like his distant cousin, Albert E. Gallatin, was born to a distinguised New York family-the Bronx's Morrisania is named for an ancestor. He studied at Groton Prep before joining the rolls of Yale University. While editing the Yale Literary Magazine, he develped a close working relationship with Gallatin in 1927, and the two toured Paris together that year. By his graduation, Morris's literary aspirations had taken a supporting role to painting, which he pursued at the Art Students League under John Sloan and Kenneth Hayes Miller. Sloan and Miller are remembered as conservative realists, but Sloan in particular must have imparted some of his progressive philosophy upon the young painter. 

In 1930, Morris left for Paris, studying under Fernand Léger at the Academie Moderne. On this and his visits from 1933 to 1935, Gallatin introduced Morris to Picasso, Braque, and Brancusi. 1935 was a banner year for Morris: he curated the Museum of Modern Art's first Léger retrospective and penned the catalogue essay-and he marries Suzy Frelinghuysen, herself a painter and socialite of some renown. He launched Plastique, a magazine devoted to abstract art with comment from himself and Charles Green Shaw. Morris and Frelinghuysen joined early talks that would develop into the American Abstract Artists group. This group launched its first exhibition the following April, and later in 1937, Morris helped organize Five Contemporary American Concretionists, in partial response to the Museum of Modern Art's survey of abstraction that omitted contemporary Americans. Morris helped revive the foundering Partisan Review, taking over as critic in 1938. Where Plastique found only a narrow audience, the Partisan Review would continue for decades, launching the careers of the most important critics of the mid-twentieth century, Clement Greenberg chief among them.

Estelle (Suzy) Frelinghuysen descended from prominent lineage, her family tree boasted a Secretary of State and a senator from New Jersey, where she was born in 1911. She studied at Miss Fine’s School in Princeton, where tastes in art ran conservative; early voice lessons suggested a promising talent, which would eventually bring a career in opera. She married George L. K. Morris at age twenty-three in January 1935. This same year she helped Morris and others found the American Abstract Artists (AAA) group. When her painting career was at its zenith, she received critical praise for both her painting and for her singing (as Suzy Morris). Her career on stage continued until medical problems in 1951 when she retired from the City Center Opera.  

She showed in 1937 at Paul Reinhardt Galleries with Morris, Gallatin, and Shaw, while another exhibition of the Park Avenue Cubists traveled to Chicago, San Francisco, and Honolulu in 1940. Peggy Guggenheim included Frelinghuysen in her Exhibition by 31 Women Artists in 1943. Her work was at the Whitney Museum of American Art and Reinhardt Gallery with the AAA in 1944, and at the Philadelphia Museum of Art in 1945. She closed the decade showing at the AAA group’s annual, and was cited in The New Yorker in 1948 by the art critic Robert M. Coates for her paintings and by the music critic Robert A. Simon for her appearance as Amneris in Verdi’s Aida. Her work was singled out alongside Josef Albers’s in a 1950 exhibition at New School for Social Research with the AAA, cementing her legacy as one of the important abstract painters of the mid-century. 

Charles Green Shaw hailed from Woolworth stock but was raised by his uncle after he was orphaned at a young age. A gifted writer and draftsman, he studied architecture at Yale University, where he joined a circle of high society with classmates such as Cole Porter. Shaw began writing humor for The Yale Record. He brought his society parodies to The New Yorker and won the respect of F. Scott Fitzgerald for his novel, Heart in a Hurricane. Graduate work at Columbia University was interrupted by classes at the Art Students League under Thomas Hart Benton. All of the Park Avenue Cubists had realist instructors, but Benton was the most committed to abstraction. Having begun his career with experiments in Synchromism, Benton continued to teach abstraction as a tool of visual investigation, and Shaw absorbed the same lessons as Benton’s most famous student, Jackson Pollock. Shaw closed the twenties with a tour of Europe which lasted until 1932. Upon returning to New York City, he committed himself to abstract art, describing his work in terms of the “plastic polygon” in 1933. His first solo exhibition the following year at Curt Valentin Gallery preceded meeting his ultimate champion in Albert E. Gallatin in 1935. Gallatin gave Shaw a monographic exhibition, writing, in the New York Evening Post, that “Mr. Shaw is doing the most important work in abstract painting in America today.” Gallatin’s trusted lieutenant, George L. K. Morris, curated the show at the Gallery of Living Art, the first solo show at Gallatin’s museum. Morris’s new, Gallatin-funded magazine Plastique ran articles by Shaw, formalizing the theory behind his shaped canvases and proto-pop explorations of the coming decades.