Helen Frankenthaler (December 12, 1928 – December 27, 2011) was an American abstract expressionist painter and a pivotal figure in the transition from Abstract Expressionism to Color Field painting. Born in New York City into a cultured Jewish family, she studied under Mexican artist Rufino Tamayo at the Dalton School and later at Bennington College with Paul Feeley. Her career began in the early 1950s, and she gained immediate recognition for her breakthrough work Mountains and Sea (1952), in which she pioneered the soak-stain technique—pouring thinned oil paint directly onto raw, unprimed canvas, allowing it to soak in and create luminous, fluid fields of color.

This innovation profoundly influenced the Color Field movement, inspiring artists like Morris Louis and Kenneth Noland. Frankenthaler exhibited widely, with major retrospectives at institutions including The Museum of Modern Art, the Whitney Museum of American Art, and the National Gallery of Art. She was awarded the National Medal of Arts in 2001 and was a member of the American Academy of Arts and Letters. Her work spanned six decades and included painting, printmaking, sculpture, ceramics, and set design for the Royal Ballet. She remains celebrated as one of the most significant American artists of the 20th century.