An innovative study of underage soldiers and their previously unrecognized impact on Civil War era America. The smooth faces of boy soldiers stand out in Civil War photography, their spindly physiques contrasting with the uniformed adults they stood alongside. Yet until now, scholars have largely overlooked the masses of underaged youths who served as musicians, carried wounded from the field, ran messages, took up arms, and died in both the Union and Confederate armies. Of Age is the first comprehensive study of how Americans responded to the unauthorized enlistment of minors in this conflict and the implications that followed. Frances M. Clarke and Rebecca Jo Plant offer military, legal, medical, social, political, and cultural perspectives as well as demographic analysis of this important aspect of the war. They find that underage enlistees comprised roughly ten percent of the Union army and likely a similar proportion of Confederate forces-but these enlistees' importance extended beyond sheer numbers. Clarke and Plant introduce common but largely unknown wartime scenarios. Boys who absconded without consent set off protracted struggles between households and the military, as parents used various arguments to recover their sons. State judges and the US federal government battled over whether to discharge boys discovered to be under age. African American youths discovered that both Union and Confederate officers ignored their evident age when using them as conscripts or military laborers. Meanwhile, nineteenth-century Americans expressed little concern over what exposure to violence might do to young minds, readily accepting their presence in battle. In fact, underage soldiers became prevalent symbols of the US war effort, shaping popular memory for decades to come. An original and sweeping work, Of Age convincingly demonstrates why underage enlistment is such an important lens for understanding the history of children and youth and the transformative effects of the US Civil War.