Knox's Commandments

The Golden Age of Detective Fiction was an era of classic murder mystery novels of similar patterns and styles, predominantly in the 1920s and 1930s.

The Golden Age proper is in practice usually taken to refer to a type of fiction which was predominant in the 1920s and 1930s but had been written since at least 1911 and is still being written—though in much smaller numbers—today. In his history of the detective story, Bloody Murder: From the Detective Story to the Crime Novel, the author Julian Symons heads two chapters devoted to the Golden Age as "the Twenties" and "the Thirties". Symons notes that Philip Van Doren Stern's article, "The Case of the Corpse in the Blind Alley" (1941) "could serve ... as an obituary for the Golden Age."

Many of the authors of the Golden Age were British: Margery Allingham (1904–1966), Anthony Berkeley (aka Francis Iles, 1893–1971), Agatha Christie (1890–1976), Freeman Wills Crofts (1879–1957), R. Austin Freeman (1862–1943), Michael Innes (1906–1993), Philip MacDonald (1900–1980), Dorothy L. Sayers (1893–1957), Josephine Tey (1896–1952), Anne Hocking (1890–1966), Edmund Crispin (1921-1978), Cyril Hare (1900-1958), and many more. Ngaio Marsh (1895–1982) was from New Zealand, but her detective Roderick Alleyn was British. Georges Simenon was from Belgium and wrote in French. Some of them, such as John Dickson Carr, Ellery Queen, and S. S. Van Dine, were American but had similar styles. Others, such as Raymond Chandler and Dashiell Hammett, had a more hard-boiled, American style.

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