Late Antiquity (4th–7th centuries CE) encapsulates the final phase of the Roman Empire, characterized by profound cultural, religious, and political transformations. The period began with significant reforms under Diocletian (284–305 CE), who addressed overexpansion by abandoning less valuable territories, fortifying frontiers, reorganizing provinces, and separating civilian and military functions. This empowered military commanders (duces), creating a more autonomous and influential military class. Constantine (306–337 CE) built on these reforms, introducing the solidus, a 4.5-gram gold coin that ensured monetary stability and outlasted the empire, with millions circulated. He also established Constantinople as a second capital, necessitating a new Senate and expanding the governing classes. These changes stimulated economic growth, evidenced by investments in rural estates, industrial installations (e.g., oil presses, glass factories), and advanced technologies like screw presses and water-mills. The revival of long-distance trade with the East further bolstered prosperity, particularly in the eastern provinces.
Culturally, the period saw the Christianization of the empire, a gradual process following Constantine’s adoption of Christianity as the state religion in the 4th century. The empire’s traditional polytheistic culture, encompassing Roman, Greek, and eastern deities, coexisted with Judaism, which was diverse and not monolithic. Christian bishops enforced stricter beliefs, reducing the fluidity between religious communities, though polytheism persisted longer in the western provinces. The rise of Islam in the 7th century, described as the “greatest political revolution” in the ancient world, began with the unification of Arabian tribes under the emerging Islamic state. By 642 CE, within a decade of Prophet Muhammad’s death, Arab conquests had seized large parts of the eastern Roman and Sasanian empires, eventually extending to Spain, Sind, and Central Asia.
Economically, the East enjoyed urban prosperity and population growth until the 6th century, despite the plague of the 540s. Papyri from Egypt reveal an affluent society with widespread money use and estates generating vast incomes, such as 2.5 million solidi (35,000 lbs of gold) annually under Justinian (527–565 CE). The Near East’s countryside was more developed in the 5th–6th centuries than in later periods. In contrast, the West fragmented as Germanic groups (Goths, Vandals, Lombards) established post-Roman kingdoms, including the Visigoths in Spain (destroyed by Arabs, 711–720), Franks in Gaul (511–687), and Lombards in Italy (568–774). These kingdoms marked the transition to the medieval world.
Justinian’s reign represented the peak of eastern prosperity, with successful campaigns like the recapture of Africa from the Vandals (533 CE). However, his recovery of Italy from the Ostrogoths devastated the region, facilitating the Lombard invasion. Renewed wars with the Sasanian Empire, which invaded eastern provinces like Egypt, weakened the empire. By the 620s, Byzantium (the evolving name for the eastern Roman Empire) briefly recovered these territories, but the rapid Islamic conquests from Arabia soon delivered a decisive blow, reshaping the ancient world’s political landscape.