Rome traditionally expels its last king, Lucius Tarquinius Superbus, abolishing the monarchy and inaugurating the republican system centered on annually elected magistrates.
Rome’s earliest written legal code is traditionally dated to 451–450 BCE. Publicly posting the Twelve Tables helped standardize legal procedure and reduce patrician control over unwritten customary law.
The Lex Canuleia (445 BCE) restores the right of legal marriage (conubium) between patricians and plebeians, an important step in easing formal status barriers within the republic.
The Lex Hortensia (287 BCE) makes resolutions of the Plebeian Council (plebiscita) binding on all Roman citizens without needing prior Senate approval, strengthening popular legislation and closing a major phase of the patrician–plebeian political struggle.
In 264 BCE, Roman intervention at Messana helps trigger the First Punic War (264–241 BCE) against Carthage, marking Rome’s transition toward sustained overseas warfare and Mediterranean power projection.
The Lex Villia Annalis (180 BCE) establishes minimum ages for candidacy to major magistracies, formalizing expectations for office-holding and the sequencing of the cursus honorum.
In 133 BCE, Tiberius Sempronius Gracchus holds the tribunate and pursues agrarian reform. The ensuing conflict with senatorial opponents is widely treated as a major escalation in late-republican political violence and polarization.
Gaius Gracchus serves as tribune in 123–122 BCE, renewing agrarian efforts and proposing broader reforms that challenged senatorial dominance, further intensifying factional conflict in republican politics.
A major rebellion by Rome’s Italian allies begins in 91 BCE (often dated 91–88/87 BCE overall). The conflict pressures Rome to extend citizenship more broadly and reshapes the republic’s political community.
After victory in civil conflict, Sulla is established as dictator in 82 BCE and undertakes a program of constitutional reforms intended to strengthen senatorial authority and constrain popular magistracies such as the tribunate.
In 67 BCE, the lex Gabinia grants Pompey extraordinary command authority over the Mediterranean to combat piracy, illustrating the late republic’s growing reliance on exceptional, individualized commands.
Between 60 and 59 BCE, Julius Caesar, Pompey, and Crassus form the informal political alliance known as the First Triumvirate, enabling coordinated action to overcome senatorial opposition and steer elections and legislation.
Caesar crosses the Rubicon in January 49 BCE, bringing troops into Italy in defiance of legal norms and triggering civil war—an inflection point in the republic’s collapse.
On 15 March 44 BCE, Julius Caesar is assassinated by a senatorial conspiracy. The killing fails to restore stable republican governance and accelerates renewed civil conflict.
On 27 November 43 BCE, the Second Triumvirate (Antony, Octavian, Lepidus) is formally constituted by law (lex Titia) as an extraordinary magistracy with sweeping powers, further sidelining traditional republican checks.
At the Battle of Actium (2 September 31 BCE), Octavian defeats Antony and Cleopatra in a decisive naval engagement, paving the way for Octavian to become the undisputed ruler and to end the republic’s civil-war era.
Roman Republic (509–27 BCE)
