Dear Mr. Feavearyear,
Thank you for posting your request on History Hub!
According to the American Battlefield Trust’s article Children of the Civil War: On the Battlefield, the minimum enlistment age for the U.S. Army was legally held at 18 for soldiers and 16 for musicians, although younger men could enlist at the permission of their parents until 1862. However, many recruiters were willing to ignore these limits. The abstract of the article No Minor Matter: Underage Soldiers, Parents, and the Nationalization of Habeas Corpus in Civil War America states that many parents used habeas corpus petitions in state and federal courts to retrieve minor children who had enlisted without their consent. The National Archives at Chicago may have U.S. district court records relating to this matter. Please contact them via email at firstname.lastname@example.org.
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from the National Archives at Chicago. We apologize for this inconvenience and appreciate your understanding and patience.
We hope this information is helpful. Best of luck with your research!