The study aims at complementing the historical knowledge regarding the participation of Dr. Bucur (Hilarius) Mitrea and Dr. Ioan Arsenie within the Austrian volunteer corps in Mexico, using as sources the copies of their conduct lists preserved in the military archives of Vienna. The new data concern the battles they took part in, together with characterizations of their behavior and personality. The latter consolidate the image built by former biographers in the case of Dr. Mitrea and help to sketch a less known portrait in the case of Dr. Arsenie.