Otis Wilbra Joslyn, Jr. enlisted in the Marine Corps on February 20, 1917, at the age of 22, before the US officially declared war. During his training and throughout his time in Europe, Otis sent home letters to his family. These letters describe his experiences during training, his deployment overseas, and offer many stories from combat, the Armistice, and Occupation Force duty on the Rhine. Otis also kept the letters his father and mother sent him during the war. These, paired with Otis's letters and excerpts from a diary in which he recorded every location the 83rd Co, 6th Marine Regiment visited, provide a fascinating look into his life during his three years of service. A Poet at War aims to tell his story and the role he and his fellow Marines played in some of the most decisive battles of the war.