Who was the first actor or actress to win three Academy Awards?

By 1940, when the Oscars ceremony was only a dozen years old, character actor Walter Brennan (18941974) had already won three Best Supporting Actor awards for his performances in Come and Get It (1936), Kentucky (1938), and The Westerner (1940).

Katharine Hepburn has won four Academy Awards, for Best Actress. Ingrid Bergman won three, two for Best Actress, one for Best Supporting Actress.