There were 8 French Lieutenants in the Confederate Army.
French Units:
CONFEDERATE
12th Alabama Infantry-Company A
24th Alabama Infantry-Company H
UNION
55th New York Infantry-"Guardes Lafayettes" Some members transferred to the 38th and 40th New York Infantry
62nd New York Infantry-1 company

French-born Confederate Generals:
Maj. Gen. Camille Armand Jules Marie, Prince de Polignac
Brig. Gen. Xavier B. DeBray
Brig. Gen. Pierre Soule

French-born Colonels:
CONFEDERATE
Lt. Col. Louis Lay (6th Louisiana)
Lt. Col. P.F. de Gournay (12th Battalion, Louisiana Artillery)
Col. Aristide Gerard (13th Louisiana)
UNION
Charles W. Le Gendre (51st New York)
Charles A. de Villiers (11th Ohio)
Nikolas Greusel (36th New York)

Hope this helps.