Thank you very much for the links to the breakdown of the Army divisions. I did find in my book by General Eichelberger that his I Corps later became part of the 6th Army. Because the Buna/Gona Campaigns were such a disaster, they moved people around and renamed groups. Now I am paying attention!! Because the negatives of Dad's are not labeled, I did not know, if the van with the VI was from his training at Fort Belvoir. VI had no meaning to me in my reconstruction of the campaigns until I came across the VI van picture. I have Milner's book and I actually tried to contact Mr. Caterra last year...he was there after my dad. Rutgers Oral history department was very helpful with my search. Thank you for taking the time to explain and link. I spent 1.5 years in Berrien Springs MI. at Andrews University, a Seventh Day Adventist university. Michigan was very friendly!! Gorgeous, agricultural area!
Janet B-W
Basically to keep it simple, Army Groups and Corps were top echelon organizations, and a division, etc. would be part of that organization. In your father's case, his unit was under VI Army jurisdiction.
In my father's case in Europe, he was always under either VI Corps, or 5th or 7th Armies, depending on the operation.
Here's a link in the research section regarding the the organization and size of units, etc.