The summer and fall campaigns of 1863 marked the pivotal five-month-long turning point of the Civil War. Famous and well-noted campaigns around Vicksburg, Mississippi, and Gettysburg, Pennsylvania have rightly been highlighted as turning-point moments. Less well-known, however, are the campaigns that unfolded in Middle and East Tennessee between June and November, 1863. Despite being eclipsed by the dramatic surrender of the Confederates’ last bastion on the Mississippi River and by the stunning defeat of Lee’s Army in Pennsylvania, the 1863 Tennessee campaigns initiated broad military, logistical, political, and social changes that transformed the Confederacy’s capacity to make war, unleashed the transformative power of the Emancipation Proclamation, freed white Unionists from the control of Confederate authority thus making available a tremendous untapped reservoir of manpower, and opened a violent and bloody guerrilla war that raged for years after the end of the war. The campaign also transformed the landscape where the armies concentrated and set in motion more than a century of environmental catastrophe in some parts of Tennessee. Finally, in creating a memorial landscape in the late 1880s and 1890s that became the model for the nation’s National Military Parks the veterans of the 1863 Tennessee campaigns set the tone and created the legal foundations that shaped and continue to shape the way Americans remember and commemorate the Civil War.