Name: John B. Cunningham
Side: Confederate
Regiment State/Origin: Tennesee
Regiment Name: 26 Tennessee Infantry. (3 East Tenn. Vols.)
Regiment Name Expanded: 26th Regiment, Tennessee Infantry (3rd East Tennessee Volunteers)
COMPANY: I
Rank In: Private
Rank In Expanded: Private
Rank Out: Private
Rank Out Expanded: Private
Film Number: M231 roll 11

Is this the same guy?

Name: John B. Cunningham
Side: Union
Regiment State/Origin: Tennesee
Regiment Name: 9 Tennessee Cavalry
Regiment Name Expanded: 9th Regiment, Tennessee Cavalry
COMPANY: I
Rank In: Private
Rank In Expanded: Private
Rank Out: Private
Rank Out Expanded: Private
Film Number: M392 roll 4

According to his pension file, it is:
Cunningham, John B.
Co I, 11th Tenn Cav
Co I, 9th Ten Cav
1890, July 24 Application # 717572 Certificate # 596524 State: Tenn

Tennessee Marriages, 1851-1900
Name: JOHN B. CUNNINGHAM
Spouse: LUCRETIA McNALLY
Marriage Date: 30 Dec 1866
County: Roane
State: TN

JR