Kammala jumla mai zuwa: Lokacin da yakin basasa ya ɓarke, Kirkland ya fara zama kyaftin a cikin sojojin Confederate sannan kuma aka zaɓe shi a matsayin colonel na 11th North Carolina Volunteers, daga baya aka sanya shi 21st North Carolina, a watan Yuni 1861. Ya umurci rundunarsa a Manassas na farko a matsayin wani ɓangare na Brig. Janar Milledge Bonham, amma ba a yi amfani da shi ba. A watan Oktoba, an sanya 21st North Carolina zuwa brigade na Isaac Trimble kuma a cikin bazara mai zuwa, ya shiga cikin Stonewall Jackson na Shenandoah Valley Campaign. An harbe Kirkland a cikin kwatangwalo biyu a lokacin
Yaƙin farko na Winchester, yana sanya shi daga aiki na watanni da yawa. A lokacin da yake farfadowa, Kirkland ya zama shugaban ma'aikatan Patrick Cleburne a lokacin yakin Murfreesboro a watan Disamba na 1862.