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

Walter Andrew Brennan (July 25, 1894 – September 21, 1974) was an American actor. He won the Academy Award for Best Supporting Actor in 1936, 1938, and 1940, making him one of only three male actors to win three Academy Awards.

Film historians and critics have long regarded Brennan as one of the finest character actors in motion picture history. While the roles he was adept at playing were diverse, he is probably best remembered for his portrayals in Western movies, such as Judge Roy Bean in 'The Westerner', trail hand Nadine Groot in 'Red River', and Deputy Stumpy in 'Rio Bravo'. He was the first actor to win three Academy Awards and remains the only person to have won Best Supporting Actor three times.