I do not know what they were doing at Hopkinsville December 16, 1864 as Col. Caudill with the 10th Kentucky Mounted Rifles was working in SW Virginia near Marion at the time.

I suspect they enlisted sometime in 1864 as the last Company A muster roll was dated December 31, 1863. Co. A, 13th Regiment Kentucky Cavalry, formerly known as Co. A, 10th Regiment Kentucky Mounted Rifles.

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R. J. Whitfield, Private, Company A, 13th Regiment Kentucky Cavalry, captured at Hopkinsville, Ky. December 16, 1864, arrived Military Prison, Louisville, Ky. December 20-25, 1864, sent to Camp Chase, Ohio December 26, arriving next day, died of Measles April 23, 1865, buried in grave No. 1906, 1/3 mile South of Camp Chase

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James M. Whitfield, Private, Company A, 13th Regiment Kentucky Cavalry, captured at Hopkinsville, Ky. December 16, 1864, arrived Military Prison, Louisville, Ky. December 20-25, 1864, sent to Camp Chase, Ohio December 26, arriving next day, died of Pneumonia April 7, 1865, buried in grave No. 1828, 1/3 mile South of Camp Chase

This regiment was known at various times as Caudill’s Regiment Kentucky Infantry, 10th Regiment Kentucky Infantry, 10th Regiment Kentucky Mounted Riflemen, and 11th Regiment Kentucky Mounted Infantry. The 11th Regiment Kentucky Mounted Infantry became the 13th regiment Kentucky Cavalry by S. O. No. 44, A. & I. G. O. dated February 22, 1865

M319: Compiled Service Records of Confederate Soldiers Who Served in Organizations from the State of Kentucky