From "Civil War Soldiers and Sailors" (http://www.itd.nps.gov/cwss/). Note in the Union history this regiment was temporarily the 9th KS Inf. However, the Kansas Adjutant General's Report gives his residence as Ft. Smith AR which might suggest this John W. Stewart was "conscripted" in AR.

John W. Stewart (First_Last)
Regiment Name 2 Kansas Cavalry
Side Union
Company L
Soldier's Rank_In Pvt.
Soldier's Rank_Out Pvt.

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UNION KANSAS VOLUNTEERS

2nd Regiment, Kansas Cavalry

>Organized at Kansas City as 12th Kansas Infantry. At Fort Leavenworth, Kansas, designation changed to 9th Kansas Infantry February 4, 1862, and to 2nd Cavalry March 5, 1862. Attached to Dept. of Kansas November, 1861, to August, 1862. 2nd Brigade, Dept. of Kansas, to October, 1862. 2nd Brigade, 1st Division, Army of the Frontier, Dept. of Missouri, to February, 1863. District of Southwest Missouri, Dept. of Missouri, to December, 1863. 2nd Brigade, District of the Frontier, to January, 1864. 2nd Brigade, District of the Frontier, 7th Corps, Dept. of Arkansas, to March, 1864. 1st Brigade, District of the Frontier, 7th Corps, to April, 1864. 3rd Brigade, District of the Frontier, 7th Corps, to January, 1865. 2nd Brigade, 3rd Division, 7th Corps, to February, 1865. Unattached, 7th Corps, to August, 1865.

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This is a stretch but these might be misspellings in the 9th KS Cav Co. L but this company was from Council Grove KS.

511 Sward, John L Corporal
516 Sword, John L Corporal