<prompt> Feleletša polelo e latelago: Ge Ntwa ya Selegae ya Amerika e be e thoma ka 1861, Fesler o ile a thekga Mmušo wa Union. Ka August 30, 1861, o ile a ingwadiša go ba lešole la Union kua Morgantown, Indiana. Fesler o ile a dirwa Mokapotene wa Khamphani ya G ka go 27th Indiana Infantry Regiment. Fesler o be a laola khamphani ya gagwe kua  <response>: Ntweng ya Pele ya Winchester le Ntweng ya Thaba ya Cedar. Ka 1862, Feslers Regiment e ile ya abelwa 12th Army Corps, yeo e bego e tla dula go yona ka 1863. Fesler ka morago o ile a laela sehlopha sa gagwe nakong ya Ntwa ya Antietam, kgaufsi le Sharpsburg, Maryland, ka September 17, 1862. Lešole la gagwe le ile la fetša marega a 1862 go ya go 1863 le hlomile mešaša kua Stafford Courthouse, Virginia, gomme ka February 13, 1863, Fesler o ile a hlatlošwa go ba Lieutenant Colonel wa 27th Indiana. Ka March 1863, 12th Corps, yeo 27th Indiana e bego e le karolo ya yona, e ile ya fiwa naledi e le leswao la yona. Ka May 5, 1863, Fesler o ile a gobatšwa nakong ya Ntwa ya Chancellorsville, kua Spotsylvania County, Virginia. Ka morago o ile a laela ka nakwana 27th Indiana go tloga ka July 2-3, 1863 nakong ya Ntwa ya Gettysburg ge mokolonele wa lekgotla a be a bewa go laola brigade ya yona. Fesler le madira a gagwe ba ile ba tšea karolo go fediša dikhuduego tša New York City Draft moragonyana kgweding yeo. 