Cate Blanchett portrayed the woman who was named by which group as the greatest female star of Classic Hollywood Cinema?
Cate Blanchett:  Her portrayal of Katharine Hepburn in Martin Scorsese's 2004 film "The Aviator" brought her critical acclaim and many accolades, including the Academy Award for Best Actress in a Supporting Role, making her the only actor to win an Oscar for portraying another Oscar-winning actor. Katharine Hepburn:  In 1999, Hepburn was named by the American Film Institute as the greatest female star of Classic Hollywood Cinema.
American Film Institute