Approximately 12,000 Union troops fought in the April 1864 battles of Sabine Cross Roads and Pleasant Hill in Louisiana. The diary covers the period December 1863 through 1864, discussing the battles and the Red River Campaign that followed. The purpose of this work is to let the words of Addison describe what was going on in his world and, through annotation of his diary (in boldface) to put his experiences into perspective with what others were doing during that time. The purpose was to also learn about the men mentioned in the diary. What were their experiences during the war? What were their lives like after the war? Chapters include: Background: Robert M. Addison - family, Wisconsin Twenty-third Infantry, Battles, and, The Mississippi River Fleet; Civil War Diary; Friends and Acquaintances; and, Suggestions for Further Reading. An index to full names, places and subjects complete this work.