structural:expansion
Economy and administration

As was the case under Justinian's predecessors, the Empire's economic health rested primarily on agriculture. In addition, long-distance trade flourished, reaching as far north as Cornwall where tin was exchanged for Roman wheat. Within the Empire, convoys sailing from Alexandria provided Constantinople with wheat and grains. Justinian made the traffic more efficient by building a large granary on the island of Tenedos for storage and further transport to Constantinople. Justinian also tried to find new routes for the eastern trade, which was suffering badly from the wars with the Persians.

One important luxury product was silk, which was imported and then processed in the Empire. In order to protect the manufacture of silk products, Justinian granted a monopoly to the imperial factories in 541. In order to bypass the Persian landroute, Justinian established friendly relations with the Abyssinians, whom he wanted to act as trade mediators by transporting Indian silk to the Empire; the Abyssinians, however, were unable to compete with the Persian merchants in India. Then, in the early 550s, two monks succeeded in smuggling eggs of silk worms from Central Asia back to Constantinople, and silk became an indigenous product.

Gold and silver were mined in the Balkans, Anatolia, Armenia, Cyprus, Egypt and Nubia. At the start of Justinian I's reign, he had inherited a surplus 28,800,000 solidi (400,000 pounds of gold) in the imperial treasury from Anastasius I and Justin I. Under Justinian's rule, measures were taken to counter corruption in the provinces and to make tax collection more efficient. Greater administrative power was given to both the leaders of the prefectures and of the provinces, while power was taken away from the vicariates of the dioceses, of which a number were abolished. The overall trend was towards a simplification of administrative infrastructure. According to Brown (1971), the increased professionalization of tax collection did much to destroy the traditional structures of provincial life, as it weakened the autonomy of the town councils in the Greek towns. It has been estimated that before Justinian I's reconquests the state had an annual revenue of 5,000,000 solidi in AD 530, but after his reconquests, the annual revenue was increased to 6,000,000 solidi in AD 550.

Throughout Justinian's reign, the cities and villages of the East thrived, although Antioch was struck by two earthquakes (526, 528) and sacked and evacuated by the Persians (540). Justinian had the city rebuilt, but on a slightly smaller scale.

Despite all these measures, the Empire suffered several major setbacks in the course of the 6th century. The first one was the plague, which lasted from 541 to 543 and, by decimating the Empire's population, probably created a scarcity of labor and a rising of wages. The lack of manpower also led to a significant increase in the number of "barbarians" in the Byzantine armies after the early 540s. The protracted war in Italy and the wars with the Persians themselves laid a heavy burden on the Empire's resources, and Justinian was criticized for curtailing the government-run post service, which he limited to only one eastern route of military importance.