Produced a Broadway play before serving as an officer with Army Intelligence in WWI and a staffer with President Wilson's negotiating team at the Paris Peace Conference.
Wanger went on to become a producer with Paramount, finally attaining the position of production chief. He served in similar posts with Columbia and MGM before establishing himself as an independent producer, shepherding such excellent films as the Garbo vehicle, "Queen Christina" (1933), John Ford's classic western, "Stagecoach" (1939), Hitchcock's "Foreign Correspondent" (1940), Fritz Lang's "Scarlet Street" (1945) and the sci-fi melodrama, "Invasion of the Body Snatchers" (1955).
Wanger was married to second wife Joan Bennett from 1940, a union not without scandal. In 1951, a jealous Wanger shot Bennett's agent, Jennings Lang, in the groin; Wanger was convicted and served a short jail sentence. He and Bennett were reconciled in 1953 and he widowed her in 1968.