Foundation trenches are often the only remains of interiors once filled with life. This is painfully true of the Roman frontier. While research on civilian housing has progressed recently, the role of built environment in the life of the military is still mainly a mystery. This study hopes to shed some light on the issue by looking at architecture of commanding officers’ houses – the praetoria. The study deploys two drastically different research methods and takes advantage of what is preserved of the military life in literary sources and on the tombstones of the officers. The dissertation concludes that there was a correlation between the set up of praetoria and the social structures of the Roman army.