Helen Frankenthaler is an American

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 abstract expressionist painter. She is a major contributor to the history of postwar American painting. Having exhibited her work in six decades she has spanned several generations of abstract painters while continuing to produce vital and ever-changing new work. She began exhibiting her large-scale abstract expressionist paintings in contemporary museums and galleries in the early 1950s.