in the 5th and 6th centuries: the Theodosian code (438) and the Corpus Juris Civilis (528–39). These compilations of Roman laws dating from the 4th century contain numerous imperial decrees relating to all aspects of the regulation and administration of the late army. De re militari is a treatise on Roman military affairs by Vegetius, a late 4th or early 5th-century writer, and contains considerable information on the late army, although its focus is on the army of the Republic and Principate. However, Vegetius (who wholly lacked military experience) is often unreliable. For example, he stated that the army abandoned armour and helmets in the later 4th century (offering the absurd explanation that this equipment was too heavy), which is contradicted by sculptural and artistic evidence. In general, it is not safe to accept a statement from Vegetius unless it is corroborated by other evidence. Scholars of the late army have to contend with a dramatic diminution of the epigraphic record in the 3rd and 4th centuries, compared with the 1st and 2nd centuries. Diplomas were no longer issued to retiring auxiliaries after 203 (most likely because almost all were already Roman citizens by then). In addition, there was a huge reduction in the number of tombstones, altars and other dedications by Roman servicemen. Official stamps of military units on building materials (e.g., tiles) are much rarer, but this trend should probably not be seen as indicating a decline in the army's administrative sophistication. Papyrus evidence from Egypt shows that military units continued to keep detailed written records in the 4th century (the vast bulk of which are lost due to organic decomposition). Most likely, the decline in inscriptions is due to changing fashion, in part influenced by the increase in barbarian recruits and the rise of Christianity. The dearth of inscriptions leaves major gaps in our understanding of the late army and renders many conclusions tentative. The seminal modern study of the late army is contained in The Later Roman Empire, 284-602 (LRE) by the "high priest" of late Roman studies, A.H.M. Jones. Because of its wealth of detail and documentary references, this 1964 publication remains an essential tool for all scholars of the period. However, its primary weakness is its age, for a considerable amount of archaeological work and other relevant scholarship has transpired in the decades since its publication. Evolution of the 4th-century army Background: the army