In Late Antiquity, Philippopolis was an important stronghold, but was sacked in 250 during the Crisis of the Third Century, after the Siege of Philippopolis by the Goths led by Cniva. After this the settlement contracted, though it remained a major city, with the city walls rebuilt and new Christian basilicas and Roman baths constructed in the 4th century. The city was again sacked by the Huns in 441/442, and the walls were again rebuilt. Roman Philippopolis resisted another attack, by the Avars in the 580s, after the walls were renewed yet again by Justinian the Great ().