Decline, collapse, or transformation? Hadrian's Wall in the 4th- 5th centuries AD

The collapse and end of Roman Britain remains a topic of interest and debate, related to conceptual issues found in the disciplines ofboth archaeology and history. The collapse of Hadrian's Wall and the frontier ofnorthern England as a region also have yet to be adequately explained. Excavations on Hadrian's Wall over the past 25 years have revealed excellent evidence for late Roman military occupation as well as sub-Roman occupation at a number of sites (e.g. South Shields, Newcastle, Vindolanda, Birdoswald, and Carlisle). While each site has been considered individually, there has been limited comprehensive treatment. When all ofthese sites have been examined together, scholars have presented models oflimited use, due to their reliance on historical frameworks. A review ofthe organization ofthe late Roman military and the concept of frontiers suggests that a theoretically based perspective would generate more useful models for understanding the decline and collapse ofRoman frontiers. Community studies, with particular emphasis on military communities, are applied to the limitanei and late Roman frontier archaeology. A synthetic evaluation ofoccupation and activity along Hadrian's Wall from the 4th to 5th centuries AD was undertaken to consider the problem oflate Roman frontier collapse and transformation. Detailed case studies ofthree sectors ofHadrian's Wall indicated that there were more than 10 traits typical oflate Roman military sites. Extending detailed examination.to all the forts on the Wall and a number of forts throughout northern England revealed that these traits are found at all forts occupied in the later 4th century. Considered individually or en masse, these traits indicate the changing nature of military occupation ofnorthern England through the 4th century. The changing role of Hadrian's Wall through the 4th century is summarized, and a number ofinterpretations are provided by which to understand the archaeological evidence, followed by recommendations for future research.