Samuel Lewis Francis was born on June 25, 1923, in San Mateo, California. He began painting in 1944 after being diagnosed with spinal tuberculosis, resulting from a U.S. Army Air Corps accident. In 1947 he studied privately with painter David Park, and soon gave up his intended medical studies.
He experimented with the dominant and emerging styles of the late 1940s, particularly Abstract Expressionism and Surrealism, eventually developing a personal style of abstraction focused on dripping, cell-like forms, an allover instability, and sensitivity to color and light, as in Opposites (1950). In 1950 Francis moved to Paris and attended the Atelier Fernand Léger, where he was exposed to the work of Pierre Bonnard and Henri Matisse, which reinvigorated his interest in light and vibrant color, visible in his 1953 painting Big Red. A visit to Japan in 1957 coincided with an opening up of expanses of white space in much of his work, and his subsequent move to a larger studio in Paris resulted in the production of large-scale paintings and mural commissions, including a 1959 painting for the Chase Manhattan Bank, New York.
Francis returned to California in 1962 and resumed painting with combinations of bright colors. In the late 1960s, however, color increasingly vanished from his canvases. In 1973 he formed a lithography production company, which published his own prints. Over the next decades, Francis's style in painting and print production evolved from the depiction of bright, centrally placed shapes evocative of Tibetan mandalas (influenced by Jungian psychology) to his late-1970s exploration of more severe grid structures to a 1980s fascination with snakelike forms and colorful drips.
His final decades of artistic production paralleled a succession of publishing, nonprofit, and visionary enterprises: in addition to his lithography studio, Francis formed a wind harvesting and alternative energy company in 1975; formed the Lapis Press, which focused on eclectic scholarship, in 1984; created a naturopathy-based medical research center in 1987; and founded the Sam Francis Art Museum in 1990 to perpetuate his artistic legacy and support charitable donations. Francis died on November 4, 1994, in Santa Monica, California.