Possible Clues:

• No cello (anag.)
• Officer junior to a brigadier
• Rank below brigadier general
• Soldier, an officer not entirely feeling the loss of his company
• General's underling
• Mark, the Spanish officer
• Silver eagle wearer, in the military
• Army officer ranking below a brigadier
• A final piece of wallpaper, endless rolls around next to Mark, he finished off layer upon layer
• Corny-sounding rank