Marka dagaalkii sokeeye bilaabmo 1861, Smith wuxuu adeegayey sida caawiye de xerada in Illinois Governor Richard Yates. Bishii Diseembar 26, 1861 waxaa loo magacaabay kornayl ka tirsan Guutada 45aad ee Ciidanka iskaa wax u qabso ee Illinois, iyadoo darajada dib loo dhigay 23kii Luulyo 1861 si loogu beddelo Kornaylkii hore ee iska casilay guddiga gobolkiisa markii guutada ay gashay adeegga Federaalka. Wuxuu hogaaminayay gudihiisa dagaalada Fort Henry, Fort Donelson iyo Shiloh. Bishii Nofeembar 29, 1862 waxaa loo dalacsiiyay sarkaal guuto oo ka tirsan kuwa iskaa wax u qabso ee Mareykanka. Wuxuu si kooban u amray guuto ka hor inta uusan qaadan amarka qeybta 8aad, XVI Corps. Markii Ulysses S. Grant uu bilaabay ololihiisii ugu dambeeyay ee ka dhanka ahaa Vicksburg, Smith waxaa loo magacaabay inuu hoggaamiyo Guutada 1aad, Qaybta 3aad, XVII Corps. Wuxuu ka qayb qaatay dagaaladii Port Gibson
Raymond, Champion Hill iyo weeraradii ka dhacay Vicksburg. Bishii Juun, 1863, intii lagu jiray go'doominta Vicksburg, Smith waxaa loo doortay inuu bedelo Gen. Isaac F. Quinby oo ah taliyaha qeybta 7-aad, XVII Corps ka dib markii Quinby uu xanuunsaday oo uu qaatay fasax. Bishii Sebtember, 1863 Smith waxaa loo wareejiyay amarkii qeybta 2aad, XVII Corps qeybtiisa waxaa loo diray William T. Sherman si ay gacan uga geysato gurmadka Chattanooga. Intii lagu guda jiray dagaalkii Missionary Ridge, Smith wuxuu ka qeyb qaatay weeraradii ka dhanka ahaa garabka midig ee Confederate ee Tunnel Hill.