His records indicate a number of different dates and locations. My best bet based on his transfer as a POW is that he
was captured February 14, possibly in the vicinity of Natchez, Miss.

Nathaniel Armistead, age 22, Private, Company D, 3rd Regiment, Texas Cavalry, enlisted May 25, 1861 at Ladonia,

captured near Natchez February 14, 1864 [card 12]
captured near Natchez February 14, 1863 [card 13]
captured at Waterproof January 14, 1864 [card 14]
captured at Ten Parrish, La. January 31, 1864
captured at Waterproof, La. January 14, 1863 [card 16]

forwarded from Vicksburg, Miss., to Cairo, Ill. February 27, 1864

received at Camp Douglas, Ill. prison March 7/8, 1864

applied for oath of allegiance to the US, January __, 1865

released February 15, 1865

subscribed and swore Oath of Allegiance to the U. S. at Camp Douglas February 20, 1865

Resident of Hunt County, Texas

M323: Compiled Service Records of Confederate Soldiers Who Served in Organizations from the State of Texas

.........

01 29 1864 Federal expedition from Vicksburg, MS, to Waterproof, parish of Tensas, LA, and skirmishes, as the Federals raid numerous plantations, confiscating everything of value from gold and silver to farm animals and weapons.
1/29-2/23/1864
The Chronological Tracking of the Civil War per the Official Records of the War of Rebellion, Ronald A. Mosocco, James River Publications

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