Roman Headquarters (Principia)
The headquarters of a Roman fort was the administrative and also the religious centre. In Latin the plural “Principia” was used for this building, thus emphasising its importance. In fortified forts it was situated at the centre of the fort, where the most important roads crossed, the “via praetoria” and the “via principalis”. From the middle of the 1st Century BC, the Principia had the same layout in all the forts. The building was accessed through an entrance in the large cross hall. The entrance led to the inner courtyard, around which the wings of the building were arranged. A covered passageway, the “Porticus”, surrounded the courtyard. In many headquarters there was a well or a water basin in one corner of the courtyard. Beneath the courtyards there were often water pipes and a sewer system. During excavations in some of the headquarters, the plinths of statues or altars were found in the inner courtyard.
Storage rooms and armouries were housed in the two side wings of the courtyard. Sometimes the rooms were also used as prisons. In many headquarters the most important rooms were housed in the rear section of the building. These were offices, assembly rooms, the fort’s strong room with the pay chest and orderly rooms. All the administration of a fort was done in the orderly rooms. The daily reports, morning dispatches, postings, guard lists, lists for leave of absence and marching orders were managed here. Records were created for every soldier of the respective garrison, and these contained details about years of service, promotions and pay.
Corresponding to its significance, the most important room was mostly architecturally emphasized. The standards shrine was situated in the centre of the rear section of the building; it was larger than the surrounding rooms and had a protruding roof. The standards, which were worshipped by the Romans, were kept on a raised platform in the standards shrine. A picture of the emperor also hung there. On feast days, the Roman army took the regimental standards out of the shrine, set them up in the courtyard of the headquarters and decorated them in a festive celebration. Every garrison had its own standard which had been handed over at the founding of the garrison. The foundation day was celebrated annually with the “natalis signorum” (the “birthday of the standard”). In the course of time, however, the emperor cult supplanted the standard cult more and more.