During the Confederate period for New Orleans I could only find two men that were colonels in the European Brigade.

Alphonse Ferrier, Colonel, F. and S., 1st Regt. European Brig. La. Mil. Name appears as signature to a Morning Report dated Nov. 23, 1861.

and

C. T. Buddecke, Colonel. There were also G. Della Valle, Lt. Colonel and D. W. Sherman, Major all were associated with forming the European Brigade.

Nailing down the 4th Regiment's colonel has been a little difficult.

David