Roman Empire Timeline

According to legend, Rome began with the twins Romulus and Remus, and Romulus killed his brother. Tradition placed Rome's founding at c. 753 BCE, a date Romans generally accepted by the Republic's end. Tradition named seven kings in turn, from Romulus down to Tarquin the Proud, who was Etruscan, from a family of Tarquinia. From the Etruscans the Romans took the military triumph, the toga, and other customs.

According to tradition, Tarquin ruled as a tyrant, and the Romans drove him out. Many modern historians think the monarchy fell to Porsenna, an Etruscan king who defeated Rome, rather than to a purely Roman uprising. Two consuls, elected each year, now replaced the king, and the Roman Republic began. Meanwhile, Carthage grew from a North African coastal city into a major Mediterranean power and became Rome's rival.

According to tradition, the plebeians withdrew from the city in c. 494 BCE and secured protectors of their own, the tribunes of the plebs. A Gallic force overran and plundered Rome. A measure of c. 367 BCE, one of the Licinian–Sextian laws, admitted plebeians to the consulship. Three Samnite Wars (343 BCE–290 BCE) left Rome in control of much of Italy.

In 312 BCE work began on the Appian Way, the first and most famous of Rome's great roads, linking Rome with Capua. The Lex Hortensia of 287 BCE bound every citizen to plebeian assembly decisions and ended the Conflict of the Orders. Then Tarentum, a Greek city, called in King Pyrrhus of Epirus against Rome; he brought an army to Italy. Pyrrhus's costly victories over Rome produced the phrase "Pyrrhic victory". When the Pyrrhic War ended, Rome stood as the dominant power in Italy. Its expansion in Italy then brought Rome into conflict with Carthage.

When the First Punic War came to an end, Sicily passed from Carthage to Rome. In 218 BCE Hannibal crossed the Alps with a Carthaginian army and entered northern Italy. At Cannae his army encircled and crushed a Roman force, and historians call it a classic double envelopment. Scipio then invaded North Africa, which forced Hannibal to leave Italy and defend Carthage. After Hannibal lost to Scipio at Zama, Carthage accepted peace terms and surrendered its fleet. The Third Punic War ended with Rome's destruction of Carthage and the sale of the survivors into slavery.

In 133 BCE the tribune Tiberius Gracchus championed land reform on behalf of small farmers, and his opponents killed him during a riot. Later, Sulla won a civil war, made himself dictator, and reformed the Republic's government. Caesar's conquest of Gaul gave him wealth and power. Crassus's death in 53 BCE turned the rivalry between his partners Caesar and Pompey into civil war. It began in 49 BCE, when Caesar crossed the Rubicon with his army and entered Italy.

Caesar replaced Rome's old calendar with the Julian calendar. On 15 March 44 BCE, Julius Caesar was assassinated by a group of Roman nobles. The Republic came to an end with his dictatorship. His adopted heir Octavian defeated Antony and Cleopatra at Actium on 2 September 31 BCE. After Antony and Cleopatra killed themselves, Egypt came under Roman rule in 30 BCE, ending the Ptolemaic dynasty.

In 27 BCE Augustus became the first Roman emperor. He took the title princeps, meaning first citizen, and the system he created is known as the principate. Augustus laid the foundation of the Pax Romana (c. 27 BCE–c. 180 CE), a long period of relative peace. In 9 CE Arminius destroyed three Roman legions in Germany, which ended Rome's hopes of conquering Germania east of the Rhine. A great fire ravaged Rome in 64 CE, and according to ancient sources Nero blamed the Christians.

Nero died in 68 CE, and civil war followed. Vespasian founded the Flavian dynasty after winning the war in 69 CE. During the Jewish revolt, Titus besieged Jerusalem in 70 CE, and the Second Temple itself was destroyed. In 80 CE Titus opened the Colosseum with 100 days of games, an arena built over the drained lake of Nero's Golden House. Under Trajan (98 CE–117 CE), Rome conquered Dacia and made it part of the empire, then went on to annex Mesopotamia in the east. In 122 CE Hadrian began building a frontier wall that crossed northern Britain.

From 193 CE, Septimius Severus governed as a military monarch, paying the army well to hold its loyalty. In 212 CE, Caracalla gave Roman citizenship to all the free people of the empire. Then in 224 CE the Sasanians, led by Ardashir I, overthrew the Parthians, and their new Persian empire pushed into Roman Mesopotamia.

In 235, soldiers killed Emperor Severus Alexander. Civil strife and short-lived emperors marked the next fifty years or so. The empire broke apart into breakaway Gallic and Palmyrene states until Aurelian defeated them both and reunited it. Diocletian, emperor from 284 CE to 305 CE, is credited with bringing the third-century crisis to an end and restoring orderly government. Judging the empire was too large for one ruler, he divided power among co-rulers in an arrangement called the tetrarchy. In 303 CE he ordered Christian scriptures burned and churches torn down, in what became the Great Persecution of Christians.

On 28 October 312 CE, Constantine's victory over Maxentius at the Milvian Bridge made him ruler of the West. In February 313 CE, Constantine and Licinius proclaimed the Edict of Milan; it gave Christians toleration throughout the empire. In 325 CE, Constantine summoned bishops to Nicaea to end the Arian controversy about Christ's nature. That gathering produced the Nicene Creed. Constantine dedicated Constantinople in 330 CE as his new imperial capital; it was a rebuilding of old Byzantium.

In 376 CE the Huns drove the Visigoths across the Danube into the empire; mistreated by Roman officials, they revolted. On 9 August 378 CE they defeated Valens's army at Adrianople; Valens was killed. In 380 CE Theodosius I declared Nicene Christianity the official faith; all Christians had to accept the Nicene creed. He died in 395 CE, leaving East and West to his two sons; no emperor after him ruled both halves. In August 410 CE Alaric's Visigoths plundered Rome for three days. In 476 CE Odoacer deposed the last western emperor, Romulus Augustulus, and became Italy's first king.

Justinian I ruled the eastern Roman empire, known as the Byzantine Empire, from 527 to 565 CE. He had Roman law brought together as one text, the Code of Justinian, which took its revised form in 534 CE. The Nika riots of 532 CE destroyed Constantinople's earlier church; Justinian then had Hagia Sophia built in its place.

The Fourth Crusade set out for the Holy Land, but in April 1204 CE its army seized Constantinople. The sack broke the empire into separate states, and neither it nor its capital ever regained its former greatness. In 1261, forces from Nicaea, where the empire survived in exile, retook Constantinople, and Michael VIII re-established the Byzantine Empire. On 29 May 1453 CE, the Ottoman sultan Mehmed II conquered Constantinople. Its fall ended the Byzantine Empire, the Roman Empire's eastern half, and the old Roman Empire itself.