Theodosius I in the context of "Sarmatians"

The Byzantine Empire, also known as the Eastern Roman Empire, was the continuation of the Roman Empire centred on Constantinople during late antiquity and the Middle Ages. Having survived the events that caused the fall of the Western Roman Empire in the 5th century AD, it endured until the fall of Constantinople to the Ottoman Empire in 1453. The term 'Byzantine Empire' was coined only after its demise; its citizens used the term 'Roman Empire' and called themselves 'Romans'.

During the early centuries of the Roman Empire, the western provinces were Latinised, but the eastern parts kept their Hellenistic culture. Constantine I (r. 324–337) legalised Christianity and moved the capital to Constantinople. Theodosius I (r. 379–395) made Christianity the state religion and Greek gradually replaced Latin for official use. The empire adopted a defensive strategy and, throughout its remaining history, experienced recurring cycles of decline and recovery.

The fall of the Western Roman Empire, also called the fall of the Roman Empire or the fall of Rome, was the loss of central political control in the Western Roman Empire, a process in which the Empire failed to enforce its rule, and its vast territory was divided among several successor polities. The Roman Empire lost the strengths that had allowed it to exercise effective control over its Western provinces; modern historians posit factors including the effectiveness and numbers of the army, the health and numbers of the Roman population, the strength of the economy, the competence of the emperors, the internal struggles for power, the religious changes of the period, and the efficiency of the civil administration. Increasing pressure from invading peoples outside Roman culture also contributed greatly to the collapse. Climatic changes and both endemic and epidemic disease drove many of these immediate factors. The reasons for the collapse are major subjects of the historiography of the ancient world and they inform much modern discourse on state failure.

In 376, a large migration of Goths and other non-Roman people, fleeing from the Huns, entered the Empire. Roman forces were unable to exterminate, expel or subjugate them (as was their normal practice). In 395, after winning two destructive civil wars, Theodosius I died. He left a collapsing field army, and the Empire divided between the warring ministers of his two incapable sons. Goths and other non-Romans became a force that could challenge either part of the Empire. Further barbarian groups crossed the Rhine and other frontiers. The armed forces of the Western Empire became few and ineffective, and despite brief recoveries under able leaders, central rule was never again effectively consolidated.

In modern historiography, the Western Roman Empire were the Roman Empire's western provinces, collectively, during any period in which they were administered separately from the eastern provinces by a separate, independent imperial court. Particularly during the period from AD 395 to 476, there were separate, coequal courts dividing the governance of the empire into the Western provinces and the Eastern provinces with a distinct imperial succession in the separate courts. The terms Western Roman Empire and Eastern Roman Empire were coined in modern times to describe political entities that were de facto independent; contemporary Romans did not consider the Empire to have been split into two empires but viewed it as a single polity governed by two imperial courts for administrative expediency. The Western Empire collapsed in 476, and the Western imperial court in Ravenna disappeared by 554, at the end of Justinian's Gothic War.

Though there were periods with more than one emperor ruling jointly before, the view that it was impossible for a single emperor to govern the entire Empire was institutionalized by emperor Diocletian following the disastrous civil wars and disintegrations of the Crisis of the Third Century. He introduced the system of the Tetrarchy in 286, with two senior emperors titled Augustus, one in the East and one in the West, each with an appointed subordinate and heir titled Caesar. Though the tetrarchic system would collapse in a matter of years, the East–West administrative division would endure in one form or another over the coming centuries. As such, the unofficial Western Roman Empire would exist intermittently in several periods between the 3rd and 5th centuries. Some emperors, such as Constantine I and Theodosius I, governed, if briefly, as the sole Augustus across the Roman Empire. On the death of Theodosius in 395, the empire was divided between his two infant sons, with Honorius as his successor in the West governing briefly from Mediolanum then from Ravenna, and Arcadius as his successor in the East governing from Constantinople.

The ancient Olympic Games (Ancient Greek: τὰ Ὀλύμπια, ta Olympia), or the ancient Olympics, were a series of athletic competitions among representatives of city-states and one of the Panhellenic Games of ancient Greece. They were held at the Panhellenic religious sanctuary of Olympia, in honor of Zeus, and the Greeks gave them a mythological origin. The originating Olympic Games are traditionally dated to 776 BC. The games were held every four years, or Olympiad, which became a unit of time in historical chronologies. These Olympiads were referred to based on the winner of their stadion sprint, e.g., "the third year of the eighteenth Olympiad when Ladas of Argos won the stadion". They continued to be celebrated when Greece came under Roman rule in the 2nd century BC. Their last recorded celebration was in AD 393, under the emperor Theodosius I, but archaeological evidence indicates that some games were still held after this date. The games likely came to an end under Theodosius II, possibly in connection with a fire that burned down the temple of the Olympian Zeus during his reign.

During the celebration of the games, the Olympic truce (ekecheiría) was announced so that athletes and religious pilgrims could travel from their cities to the games in safety. The prizes for the victors were olive leaf wreaths or crowns. The games became a political tool used by city-states to assert dominance over their rival city-states. Politicians would announce political alliances at the games, and in times of war, priests would offer sacrifices to the gods for victory. The games were also used to help spread Hellenistic culture throughout the Mediterranean. The Olympics also featured religious celebrations. The statue of Zeus at Olympia was counted as one of the seven wonders of the ancient world. Sculptors and poets would congregate each Olympiad to display their works of art to would-be patrons.

The Temple of Apollo, also known as Apollonion, (Greek: Ἀπολλώνιον, romanized: Apollṓnion) was a major part of the Panhellenic religious sanctuary located in Central Greece at Delphi. The temple and sanctuary at large were dedicated to one of the major Greek deities, Apollo, the god of archery, music, light, prophecy, the arts, and healing. There have been several temples built at Delphi throughout the history of the site, though the visible ruins seen in modernity are those of the temple built in the 4th century B.C.E. before its destruction under the orders of Theodosius I in 390 C.E.. During antiquity, the temple was home to the famous Greek prophetess the Pythia, or the Oracle of Delphi, making the Temple of Apollo and the sanctuary at Delphi a major Panhellenic religious site as early as the 8th century B.C.E., and a place of great importance at many different periods of ancient Greek history. References to Delphi, the sanctuary, the temple, and the prophecies of the Pythia are made throughout ancient Greek mythology and historical accounts from the periods of its use.

Alaric I (/ˈælərɪk/; Gothic: 𐌰𐌻𐌰𐍂𐌴𐌹𐌺𐍃, Alarīks lit.'ruler of all'; Latin: Alaricus; c. 370 – 411 AD) was the first king of the Visigoths, from 395 to 410. He rose to leadership of the Goths who came to occupy Moesia—territory acquired a couple of decades earlier by a combined force of Goths and Alans after the Battle of Adrianople.

Alaric began his career under the Gothic soldier Gainas and later joined the Roman army. Once an ally of Rome under the Roman emperor Theodosius, Alaric helped defeat the Franks and other allies of a would-be Roman usurper. Despite losing many thousands of his men, he received little recognition from Rome and left the Roman army disappointed. After the death of Theodosius and the disintegration of the Roman armies in 395, he is described as king of the Visigoths. As the leader of the only effective field force remaining in the Balkans, he sought Roman legitimacy, never quite achieving a position acceptable to himself or to the Roman authorities.