Joseph Milton Glasco was born on January 19, 1925, in Pauls Valley, Oklahoma, the son of Lowell Marion and Pauline Elizabeth (Suddath) Glasco. He grew up in Tyler, Texas.
During World War II, Glasco served in the United States Army from 1943 to 1946. After the war, he continued his art studies in the United States and Europe. He later settled in New York, where he became part of the city's contemporary art scene.
Glasco studied at the University of Texas at Austin in 1941–1942. After his military service, he studied at the Portsmouth Art School in England. He subsequently attended art schools in Los Angeles and the School of Painting and Sculpture in San Miguel de Allende, Mexico.
In 1949, he moved to New York City and studied at the Art Students League, where he worked with George Grosz.
Glasco established himself as a painter and sculptor in New York during the late 1940s. His first one-man exhibition was held at Perls Gallery in New York in 1950. His work was acquired by the Museum of Modern Art, and in 1952 he was included in the museum's exhibition Fifteen Americans, organized by curator Dorothy C. Miller. The exhibition also featured Jackson Pollock, Mark Rothko and Clyfford Still.
During the 1950s, Glasco exhibited widely in New York and participated in exhibitions at the Whitney Museum of American Art and other American institutions. The Whitney's records document his participation in numerous annual exhibitions from 1951 onward, as well as his inclusion in the 1991 Whitney Biennial.
After leaving New York, Glasco worked in Taos, New Mexico, and later settled in Galveston, Texas. His work developed from early figurative painting and drawing toward increasingly abstract and collage-based compositions. The Museum of Fine Arts, Houston notes that he embraced abstraction and collage techniques particularly in the 1970s and continued developing his work through the 1980s and 1990s.
His works are held in the collections of major American museums, including the Museum of Modern Art, the Whitney Museum of American Art and the Museum of Fine Arts, Houston.
Glasco was included in the Museum of Modern Art's 1952 exhibition Fifteen Americans, a landmark exhibition organized by Dorothy C. Miller that presented fifteen American painters and sculptors.
He was listed as a noteworthy artist by Marquis Who's Who, a long-established American biographical directory that publishes profiles of individuals selected for professional achievement and prominence.
Glasco was a member of the National Society Literature and the Arts.
