Key life events that influenced the writings of Ernest Hemingway include his experiences in World War I as an ambulance driver, his work as a foreign correspondent during the Spanish Civil War, and his time spent in Paris during the 1920s. Hemingway's injuries and the themes of loss and disillusionment from the war featured prominently in his early works. Additionally, his complex relationships and the challenges of masculinity found expression in novels like "The Sun Also Rises" and "A Farewell to Arms," cementing his style and thematic focus.