Specifically, the study of the progression focuses on examining Hemingway's Across the River and into the Trees for evidence of traumas' effects on Hemingway's development of narrative structure. Throughout his career, Hemingway pinpoints the importance of witnessing and experiencing war on a writer. I endeavor to demonstrate-in detail, achieved by close reading, and with solid evidence-how the imbrication of trauma in Across the River and into the Trees represents a vital moment in Hemingway's progression as a writer. My assertion, a new calculus of subjectivity and objectivity appearing in the narrative structure via the protagonist, viably counters previous critical dismissal of this text and offers new horizons for studies of form and content in Hemingway's writing.