All of the following writers wrote during the years between the First and Second World Wars EXCEPT

Langston Hughes was a central figure of the Harlem Renaissance and wrote extensively during the 1920s and 1930s. His poetry, novels, and essays from this period reflect the cultural and social dynamics of the time, placing him firmly within the specified timeframe.

Sherwood Anderson gained prominence with his 1919 work "Winesburg, Ohio," and continued to publish throughout the 1920s and 1930s. His contributions to American literature during the interwar years include influential short stories and novels that explore themes of modernity and disillusionment.

F. Scott Fitzgerald is best known for his works during the Jazz Age, particularly "The Great Gatsby," published in 1925. His writing encapsulates the spirit of the Roaring Twenties and the subsequent disillusionment of the 1930s, making him a significant voice during the interwar period.

Gertrude Stein was an avant-garde writer and a key figure in modernist literature, with her work spanning the interwar years. Her experimental prose and influence on the expatriate community in Paris were significant during this period, thus aligning her with the specified timeframe.