He was born in Los Angeles, younger brother of actor Charles Ruggles. He began his career in 1915 as an actor, appearing in a dozen or so silent films, on occasion with Charles Chaplin.
In 1917, he turned his attention to directing, making more than 50 films — including a silent film version of Edith Wharton's novel The Age of Innocence (1924) — before he won acclaim with Cimarron in 1931. The adaptation of Edna Ferber's novel Cimarron, about homesteaders settling in the prairies of Oklahoma, was the first Western to win an Academy Award as Best Picture.
Ruggles followed this success with the light comedy No Man of Her Own (1932) with Clark Gable and Carole Lombard, the comedy I'm No Angel (1933) with Mae West and Cary Grant, College Humor (1933) with Bing Crosby, and Bolero (1934) with George Raft and Carole Lombard.
He teamed with the Rank Organisation in 1946 to produce and direct London Town with Sid Field and Petula Clark, based on a story he wrote. The film — British cinema's first attempt at a Technicolor musical extravaganza — is notable as being one of the biggest critical and commercial failures in that country's film history. Ironically, Ruggles had been hired to direct it because as an American, it was thought, he was better equipped to handle a musical — despite the fact that nothing in his past had prepared him to work in the genre. It was his last film. An abridged version was released in the U.S. under the title My Heart Goes Crazy by United Artists in 1953.