For which of these films did John Ford win the Academy Award for Best Director?

John Ford, had already won Best Director Academy Award Oscars for three previous films, "The Informer" (1935), "The Grapes of Wrath" (1940), and "How Green Was My Valley" (1941).

"The Quiet Man" (1952) is director John Ford's epic romantic comedy, a loving, sentimental, nostalgic tribute to his Irish ancestry and homeland. It was filmed mostly on location in Ireland. Its screenplay was based on Frank Nugent's adaptation of Maurice Walsh's “Saturday Evening Post” in the 1933 short story “Green Rushes”.

Ford considered the comedy love story one of his favourite films.The memorable plot was about the collision course between an Irish-American boxer nicknamed 'Trooper Thornton' ( John Wayne) in the town of Innisfree, and a local bully (Victor McLaglen).They became further entangled when Thornton fell in love with the local bully’s fiesty, red-haired, sister (Maureen O'Hara) who refused to consummate her marriage without her dowry. The story was inspired by a Celtic myth about a monumental battle between two sacred kings (gods) who annually fought for the affections of a queen (or goddess).

He was nominated for Best Director for "Stagecoach" in 1939. He directed the film "The Searchers" in 1956 and the film "The Man Who Shot Liberty Valance" in 1962 without Academy success.