Diocletian’s administrative reform divided the province of Noricum in two: the northern border district, Noricum ripense, and Noricum mediterraneum, bordering Italia. The two provinces developed very differently. The towns in Noricum mediterraneum were furnished with numerous, archaeologically proven church buildings in the course of the late 4th and 5th centuries. With the exception of Teurnia that could have acted as the capital at the time, these towns were later deserted in favour of partly fortified hilltop settlements in geographically sheltered positions that were equipped with small garrisons. The Roman presence in the region was first replaced by the rule of the Ostrogoths and – at least in some places – lastly by the Lombards, until Antiquity finally came to an end around 600 AD as a result of Slavic land seizures. One of the most important developments in Noricum ripense was the Late-Antique expansion of border defence systems in forts along the Danube River and in the immediate hinterlands along the main roads. The forts increasingly served as dwelling places for the civilian population and sporadically also as bishops’residences. Towards the end of the 4th century, however, the towns shrank, losing their functions as regional centres around 400 AD. For a while at least they were populated to different degrees of density. The apparent absence of church organisation could also be a result of the fact that many settlements were deserted between the end of the 4th and beginning of the 5th centuries and that the Roman presence under Odoaker came to an end in 488 AD.