This dissertation seeks to answer three questions: 1.) Which American directors developed the film language that most accurately described the Great War; 2.) What was the life and wartime experience of each of these filmmakers that informed their work and lent their Great War films authenticity? and 3.) How did the work of these directors help shape an overall film industry ethos of the male protagonist confronting conflict? After examining 185 American directors who made films with at least a Great War subtext, I narrowed the field to those who had actually participated in the war. Of those, William A. Wellman, Howard W. Hawks, Lewis Milestone, and William K. Howard proved to be the most influential. I explore in depth how each director's early life and military experiences shaped his perception of the Great War that translated onto the screen. Although Wellman and Hawks might seem obvious choices, their backgrounds are complex, revealing, and in some ways, unexpected. Milestone's presentation of the war was shaped by a tumultuous early life in Russia and New York and his experiences in the US Signal Corps. Howard, an artilleryman, took a surprisingly different approach to depicting the Great War. Because the work of these directors directly affected not only how the war is perceived but also how Hollywood portrays men dealing with conflict, I consider them the filmmaking auteurs of the Great War.