It sounds like he was captured at Fort Archer by the V Corps. The fort was defended by James Dearing's cavalry brigade which was under one of his regimental commanders that day.
This was part of Grant's fifth offensive and was an attempt to take the Southside railroad. Later in the day the IX Corps advanced further but was repulsed in the battles at the Peeble's and Pegram's Farms. These events are covered in Richmond Redeemed by Richard Sommers.
Dearing's brigade was a good brigade but very little has been written about it. Kennedy's writings can be found in Walter Clark's multi part series on north Carolina troops in the great war.
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