Naturalism is an outgrowth of realism, a prominent literary movement in late 19th century France and elsewhere.

Naturalistic writers were influenced by the evolution theory of Charles Darwin. They believed that one's heredity and surroundings decide one's character. Whereas realism seeks only to describe subjects as they really are, naturalism also attempts to determine "scientifically" the underlying forces (i.e. the environment or heredity) influencing these subjects' actions. They are both opposed to romanticism, in which subjects may receive highly symbolic, idealistic, or even supernatural treatment. Naturalistic works often include uncouth or sordid subject matter. For example, Emile Zola's works had a frankness about sexuality along with a pervasive pessimism.

Naturalists also adopted the technique of detailed description and an eye for the minute from their immediate predecessors, the Realists.

The main proponent of naturalism in fiction was Emile Zola, who wrote a treatise on the subject ("Le roman experimental") and employed the style in his many novels. Other French authors influenced by Zola were Guy de Maupassant, Joris Karl Huysmans, and the Goncourt brothers . Stephen Crane is probably the best-known naturalistic author to have written in English.

While literary naturalism is similar in definition to the philosophical and artistic movements of the same name, these were neither concurrent with nor extremely relevant to it. The music of the period, however, was influenced to some extent by it.

Slightly before 1900, symbolism and neo-romanticism began as reactions to naturalism and realism.