Battles & Wars › Greece, Rome & Han
Roman Empire
27 BC – AD 476 (West)· Empire, kingdom or state· Europe
Well documentedSolid records, physical evidence or scientific consensus.
The Mediterranean-wide state ruled by emperors from Augustus in 27 BC; its western half fell in 476, its eastern in 1453.
See it on the Battles & Wars map →What happened
Augustus turned the Republic into a monarchy in all but name. At its peak around AD 117 the empire ran from Britain to Mesopotamia and held perhaps 50 to 70 million people. A professional army of roughly 300,000 to 400,000 guarded the frontiers, linked by paved roads. After a third-century crisis the empire was split for administration, then permanently divided in 395. The West dissolved amid migrations and invasions; its last emperor was deposed in 476. The eastern, Byzantine half lasted until 1453.
Why it matters
Its law, roads, cities, Latin language and, later, Christianity shaped Europe. Later powers, from Charlemagne to the Russian tsars, claimed to be its heirs.
How we know
Abundant: Roman histories, law codes, inscriptions, coins, roads, frontier works like Hadrian's Wall, and whole preserved cities such as Pompeii.
Still debated
Why the West fell is one of history's great debates: invasions, civil wars, money troubles, plague and climate change have all been blamed.
Inside this (11)
Connections (12)
▸Conquests of Alexander the Great spread Greek culture later absorbed by Roman EmpireMostly agreed
The connection
Alexander's conquests planted Greek cities, language and art from Egypt to Afghanistan, creating the Hellenistic world. When Rome conquered the kingdoms his generals founded, from Macedon in 168 BC to Egypt in 30 BC, it absorbed that culture. Greek stayed the common language of the eastern empire, and Roman elites studied Greek philosophy and copied Greek art.
When and how
Eastern Mediterranean, from Alexander's death in 323 BC to Rome's annexation of Ptolemaic Egypt in 30 BC, through Rome's wars with Macedon and the Seleucid kings.
How sure are we?
Greek inscriptions and papyri across the eastern empire, Roman copies of Greek statues, and the poet Horace: 'Captive Greece took captive her savage conqueror.'
Debates and open questions
How much Greek influence Roman culture already had before these conquests, through Greek cities in southern Italy, is debated.
▸Julius Caesar paved the way for Roman EmpireWell documented
The connection
Caesar showed that a general with a loyal army could override the Senate, and his dictatorship for life ended the Republic in practice. His adopted heir Octavian inherited his name, money and the soldiers' loyalty, and used them to build the imperial system Caesar had foreshadowed but never formalized.
When and how
Rome, 49–44 BC; Caesar's will, read after his murder in March 44 BC, adopted Octavian as his son.
How we know
Cicero's contemporary letters and later histories by Suetonius and Cassius Dio document the path from Caesar's dictatorship to Augustus.
Debates and open questions
Whether Caesar intended a monarchy, and whether the Republic was already doomed before him, are long-running debates.
▸Battle of Actium led to the founding of Roman EmpireWell documented
The connection
With Antony and Cleopatra dead and Egypt annexed in 30 BC, Octavian had no rival left. In 27 BC the Senate gave him the name Augustus. He kept the Republic's offices but held the real power, the army and the money. Historians conventionally date the Roman Empire from then.
When and how
Actium, September 2, 31 BC; Alexandria, August 30 BC; Rome, January 27 BC.
How we know
Augustus's own record of his deeds, the Res Gestae, inscribed in stone, plus Cassius Dio and coins celebrating the capture of Egypt.
Debates and open questions
Exactly when the Republic ended, at Actium, in 27 BC, or gradually, is partly a matter of definition.
▸Battle of the Teutoburg Forest helped fix the Rhine as the frontier of Roman EmpireWell documented
The connection
Before AD 9 Rome was organizing Germany up to the Elbe as a province. After losing three legions, Augustus pulled back. Germanicus led punishing campaigns until AD 16, but Tiberius then recalled him. The Rhine, later joined to the Danube by a fortified line, stayed the frontier, and most of Germany never became Roman.
When and how
Northern Germany, AD 9–16; Augustus, Tiberius and Germanicus on the Roman side, Arminius leading the Cherusci and allied tribes.
How we know
Tacitus and Cassius Dio describe the pullback; archaeology shows Roman sites east of the Rhine, such as the town at Waldgirmes, abandoned around this time.
Debates and open questions
Some historians argue Rome stopped mainly because Germany was poor and costly to hold, making the defeat more an excuse than the cause.
▸Battle of Adrianople helped start the crisis that toppled the western Roman EmpireMostly agreed
The connection
Adrianople destroyed much of the eastern field army and showed that a Germanic people could beat Rome inside its own borders. A treaty in 382 let the Goths settle as semi-independent allies. Their descendants, the Visigoths, sacked Rome in 410, and other settled groups carved up the West until 476.
When and how
Near Adrianople (Edirne, Turkey), August 9, 378; peace with the Goths in 382 under Emperor Theodosius I.
How sure are we?
Ammianus Marcellinus called it Rome's worst defeat since Cannae; later sources trace the Visigoths' path from this settlement to Rome and Gaul.
Debates and open questions
Some historians see Adrianople as the start of the West's fall; others stress later civil wars and politics, noting that the East survived the same shock.
▸Battle of the Yarmouk took Syria from the eastern half of Roman EmpireWell documented
The connection
Yarmouk destroyed the army Emperor Heraclius had gathered to hold Syria. He withdrew to Anatolia, and Damascus, Jerusalem and the coastal cities surrendered within a few years. The eastern Roman (Byzantine) Empire lost its richest provinces, then Egypt by 642, and shrank to a Greek-speaking state centered on Anatolia and Constantinople.
When and how
Yarmouk River valley, August 636; the Byzantine field army against the forces of the early caliphate; Jerusalem surrendered about 637–638.
How we know
Byzantine and Arab sources agree on the defeat and Heraclius's withdrawal; later coins, papyri and administrative records show Syria under caliphal rule.
Debates and open questions
Whether Byzantine rule in Syria was already fragile, because of religious disputes and exhaustion from the long war with Persia, is debated.
▸Fall of Constantinople ended the last remnant of Roman EmpireWell documented
The connection
'Byzantine' is a modern label. The empire ruled from Constantinople was the eastern Roman Empire, which outlived the West by nearly 1,000 years and whose people called themselves Romans. When Constantine XI died on the walls in 1453, a line of Roman emperors reaching back to Augustus ended. Mehmed II then claimed the title 'Caesar of Rome'.
When and how
Constantinople (Istanbul), May 29, 1453; the last emperor, Constantine XI Palaiologos, and Sultan Mehmed II. The last Byzantine fragments, the Morea and Trebizond, fell in 1460–61.
How we know
Byzantine coins, laws and documents call the state and its people Roman (Rhomaioi) until 1453, and Ottoman and Western sources recognized that claim.
Debates and open questions
Whether medieval Byzantium 'counts' as Roman is partly definition; the Holy Roman Empire and Russia, as the 'Third Rome', also claimed Rome's inheritance.
▸Punic Wars set Rome on the road to Roman EmpireWell documented
The connection
Before 264 BC Rome ruled only Italy. Fighting Carthage forced it to build a navy and take its first overseas provinces: Sicily, Sardinia, Spain and finally Africa. Victory left it the strongest Mediterranean power, soon dominant in the Greek east too. The wealth and big armies of conquest later fueled the civil wars that ended the Republic.
When and how
Western Mediterranean, 264–146 BC: Sicily, Italy, Spain and North Africa.
How we know
Polybius wrote his history to explain how Rome rose to rule the known world in under 53 years; provinces and tribute are well recorded.
Debates and open questions
Historians debate whether Rome expanded by deliberate aggression or through a chain of defensive reactions, as Roman writers claimed.
▸Hunnic Empire (Attila the Hun) ravaged both halves of Roman EmpireWell documented
The connection
In the 440s Attila's armies devastated the Balkans and extorted ever-larger gold payments from Constantinople. In 451 he invaded Gaul and was checked at the Catalaunian Plains by the Roman general Aetius and the Visigoths. In 452 he plundered northern Italy, then withdrew. By pushing peoples into the empire, the Huns also hastened the West's collapse.
When and how
The Balkans in the 440s, Gaul in 451, northern Italy in 452; Attila against emperors Theodosius II and Valentinian III.
How we know
Priscus's eyewitness account, Roman chronicles and Jordanes describe the campaigns and the treaties setting tribute.
Debates and open questions
Why Attila turned back from Italy in 452, whether because of Pope Leo I's embassy, disease, famine or Eastern Roman attacks, is debated.
▸Caesar's Civil War: the Rubicon and Pharsalus doomed the Republic, paving the way for Roman EmpireWell documented
The connection
Victory made Caesar dictator for life, ending the Republic's shared rule in practice. His murder in 44 BC set off new civil wars. His adopted heir Octavian won them, defeating Antony and Cleopatra at Actium in 31 BC, and in 27 BC became Augustus, the first emperor.
When and how
Rome and its provinces, 49–27 BC; Caesar, his assassins Brutus and Cassius, Mark Antony and Octavian.
How we know
Ancient historians from Suetonius to Cassius Dio, along with coins and inscriptions, record the shift from Republic to one-man rule.
Debates and open questions
Whether the Republic was already doomed by a century of crises, from the Gracchi to Sulla, or whether Caesar personally broke it, is a classic debate.
▸Battle of Carrhae made Parthia the eastern rival of Roman EmpireWell documented
The connection
Carrhae showed that Parthia, a horse-based empire in Iran and Mesopotamia, could beat Rome. For nearly three centuries the two fought along the Euphrates and over Armenia; emperors such as Trajan won campaigns, but Rome never held all of Mesopotamia. The Persian Sasanians, who replaced the Parthians in 224, carried on the rivalry.
When and how
Along the Euphrates frontier from 53 BC; milestones include Antony's failed invasion (36 BC), Augustus's treaty (20 BC) and Trajan's war (114–117).
How we know
Roman and Greek histories, Parthian and Roman coins, and the Prima Porta statue celebrating the returned standards record the long rivalry.
Debates and open questions
How big a threat Parthia really posed, versus Roman ambition inflating it, is debated; Parthian views survive mainly in coins and a few inscriptions.
▸Boudica's revolt nearly ended Britain's place in the Roman EmpireWell documented
The connection
Britain had been a Roman province for only 17 years when Boudica's forces destroyed its three main towns, including the new trading hub of London. Had Paulinus lost the final battle, Rome might have abandoned the island; Suetonius says Nero once considered leaving. Instead Rome stayed, ruled more cautiously, and held Britain for some 350 more years.
When and how
Southeast Britain, AD 60–61; Boudica, the governor Gaius Suetonius Paulinus, and Emperor Nero in Rome.
How we know
Tacitus and Cassius Dio describe the crisis, and burned layers under Colchester, London and St Albans show its scale.
Debates and open questions
Whether Nero's thought of leaving Britain was linked to this revolt is unclear, since Suetonius does not date it.