Modernism is not an easy term to define. Just the simple act of identifying when it begins and ends as an artistic movement is challenging. Scholars continue to debate which social and cultural changes have the largest impact on Modernism. This explanation will offer three points about Modernism that encapsulate a brief definition.
First of all, Modernism as a literary movement responds directly to the rigidity of the Victorian Era. Predictable literary norms that were popular and expected during Victorian times, were abandoned in favor of more artistic and unconventional expression. This is the time period readers link with the stream of consciousness style, as well as the confessional approach to writing that hid nothing at all about a writer or narrator's experience from readers.
Second of all, Modernism was a response to the atrocities of World War I and all of the advancement that contributed to the death and destruction caused by the war. The emotions and devastation caused by the war are linked directly with the technology that was used for the first time during the war; for example, young men with naive dreams of glory on the battlefield were subjected to the shock of machine gun warfare and gas attacks, both of which offer combatants few opportunities for old-fashioned gallantry.
Finally, Modernist literature can be characterized by experimentation that reflects a lack of faith in the old reliable traditions of the past. The traumatized emptiness of the post-World War I survivors could not be described adequately by traditional forms of writing, so new ones needed to emerge. Much of Modernist literature is so deeply personal, many readers find them completely impenetrable, much like a personal crisis can be beyond everyone's understanding, except for the person going through the pain.