What event turned American writers toward Realism, in 1914.?

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By 1914, America had grown up; in a sense, American literature had, too. The Civil War, the closing of the frontier, and indistrialiation had brought about a loss of innocence, a shift from idealism to pragmatism in the American character. In their rejection of Romanticism and the embraces of Realism, American writers reflected this change.