Frank Stella's art in the 1970s marked a significant shift from his earlier minimalist and post-painterly abstraction works. Having already established himself as a leading figure in the Minimalist art movement in the previous decade, Stella's work in the 1970s began to evolve towards a more complex, maximalist approach that incorporated relief and texture, thus defying the flatness characteristic of his earlier pieces. In the early part of the decade, Stella's art continued to explore the geometric patterns and shapes that had defined his work in the 1960s. However, as the 1970s progressed, his pieces became increasingly three-dimensional. This period saw the creation of his Polish Village series (1970-73), where Stella started experimenting with collage and relief by attaching various materials such as paper, felt, and wood to his canvases, adding a tangible depth and texture that contrasted with the optical flatness of his minimalist works​ (The Art Story)​. One of the significant milestones in Stella's career during the 1970s was his exhibition at the Museum of Modern Art (MoMA) in 1970, which marked him as the youngest artist to receive a retrospective at the institution at that time. This exhibition underscored the pivotal role Stella played in the contemporary art world and highlighted his transition from minimalism to more complex and dynamic forms​ (Wikipedia)​. Later in the decade, Stella's exploration of three-dimensionality evolved further with the Indian Bird series (1977-79), where he began to assemble painted aluminum forms that protruded from the wall, creating an interplay of shadows and depth that challenged traditional perceptions of painting as a two-dimensional medium. This period was characterized by a burgeoning interest in creating artworks that existed in a space between painting and sculpture, a theme that Stella would continue to explore in subsequent decades​ (The Art Story)​. Stella's work in the 1970s is also notable for its increasing use of color and its departure from the hard-edged style of his earlier works. The latter part of the decade saw him beginning to produce mixed-media reliefs that were not only three-dimensional but also featured sensuously colored arabesques, French curves, and other organic shapes, signaling a move away from the strictly geometric compositions of his minimalism towards more fluid and dynamic forms​ (Encyclopedia Britannica)​. By the end of the 1970s, Frank Stella's art had undergone a significant transformation, signaling a departure from minimalism towards a new complexity that integrated aspects of sculpture, collage, and painting. This period set the stage for his later work, which would continue to push the boundaries of conventional art forms and cement his status as one of the most innovative and influential artists of the 20th century.