Lott G. and James Williams enlisted in Vance's Company, 4th Arkansas Cavalry, U.S. Volunteers, at Benton, Arkansas, on November 22, 1863. Upon enlistment, Lott's age was listed as 44, James' age as 18.
Vance's Company was disbanded at Little Rock, Arkansas, on March 28, 1864, and most of the men were discharged, though some were transferred to Company A.
Here's a brief summary of the 4th Arkansas (U.S.) Cavalry --
Regiment organized at Little Rock December, 1863.
Attached to Post of Little Rock, 7th Army Corps, Department of Arkansas, to May, 1864.
Attached to 3rd Brigade, 1st Division, 7th Army Corps, Department of Arkansas, to September, 1864.
Attached to 2nd Brigade, Cavalry Division, 7th Army Corps, to February, 1865.
Unassigned, 7th Army Corps, to March, 1865.
Attached to Cavalry Brigade, Post of Little Rock, 7th Corps, to June, 1865.
Service:
Duty at Little Rock, Arkansas, until June, 1865.
Skirmish on Saline River, Arkansas, February 15, 1864.
Skirmish at Cedar Glade, Arkansas, March 1, 1864.
Scout to Benton, Arkansas, March 27-31, 1864.
Action at Mt. Elba, Arkansas, March 30, 1864.
Action at Camden, Arkansas, April 15, 1864.
Skirmishes at Dardanelle, Arkansas, May 15-17, 1864.
Operations in Arkansas against guerrillas, July 1-31, 1864.
Skirmish near Benton, Arkansas, July 6, 1864.
Skirmish in Montgomery County, Arkansas, July 11, 1864.
Skirmish at Caddo Gap, Arkansas, July 12, 1864.
Skirmishes at Fair’s Mills and Bayou Des Arc, Arkansas, July 14, 1864.
Saline River, Arkansas, July 16, 1864.
Scout to Benton, Arkansas, September 6-7, 1864.
Reconnaissance toward Monticello and Mt. Elba, Arkansas, October 4-11, 1864.
Reconnaissance to Princeton, Arkansas, October 19-23, 1864.
Skirmish on Hurricane Creek, Arkansas, October 23, 1864.
Scout from DeValls Bluff to Searcy and Clinton, Arkansas, November 9-15, 1864.
Expedition from Little Rock to Fort Smith, Arkansas, September 25-October 13, 1864.
Skirmishes at Clarksville, Arkansas, September 28 and October 9, 1864.
Skirmish at White Oak Creek, Arkansas, September 29, 1864.
Scout from Little Rock to the Saline River, Arkansas, April 26-29, 1865.
Scout from Little Rock to Bayou Metoe and Little Bayou, Arkansas, May 6-11, 1865.
Mustered out, June 30, 1865.