Jugurthine War (111–104 BC)
The Jugurthine War of 111–104 BC was fought between Rome and Jugurtha of the North African kingdom of Numidia. It constituted the final Roman pacification of Northern Africa,[71] after which Rome largely ceased expansion on the continent after reaching natural barriers of desert and mountain. Following Jugurtha's usurpation of the throne of Numidia,[72] a loyal ally of Rome since the Punic Wars,[73] Rome felt compelled to intervene. Jugurtha impudently bribed the Romans into accepting his usurpation. Jugurtha was finally captured not in battle but by treachery.
The Celtic threat (121 BC) and the new Germanic threat (113–101 BC)
Cimbrian War
In 121 BC, Rome came into contact with two Celtic tribes (from a region in modern France), both of which they defeated with apparent ease. The Cimbrian War (113–101 BC) was a far more serious affair than the earlier clashes of 121 BC. The Germanic tribes of the Cimbri and the Teutons migrated from northern Europe into Rome's northern territories and clashed with Rome and her allies. At the Battle of Aquae Sextiae and the Battle of Vercellae both tribes were virtually annihilated, which ended the threat.
Internal unrest (135–71 BC)
Roman Servile Wars
The extensive campaigning abroad by Roman generals, and the rewarding of soldiers with plunder on these campaigns, led to a general trend of soldiers becoming increasingly loyal to their generals rather than to the state. Rome was also plagued by several slave uprisings during this period, in part because vast tracts of land had been given over to slave farming in which the slaves greatly outnumbered their Roman masters. In the 1st century BC at least twelve civil wars and rebellions occurred. This pattern continued until 27 BC, when Octavian (later Augustus) successfully challenged the Senate's authority, and was made princeps (first citizen).
Between 135 BC and 71 BC there were three "Servile Wars" involving slave uprisings against the Roman state. The third and final uprising was the most serious, involving ultimately between 120,000 and 150,000 slaves under the command of the gladiator Spartacus. In 91 BC the Social War broke out between Rome and its former allies in Italy when the allies complained that they shared the risk of Rome's military campaigns, but not its rewards. Although they lost militarily, the allies achieved their objectives with legal proclamations which granted citizenship to more than 500,000 Italians.
The internal unrest reached its most serious state, however, in the two civil wars that were caused by the consul Lucius Cornelius Sulla at the beginning of 82 BC. In the Battle of the Colline Gate at the very door of the city of Rome, a Roman army under Sulla bested an army of the Roman Senate and entered the city. Sulla's actions marked a watershed in the willingness of Roman troops to wage war against one another that was to pave the way for the wars which ultimately overthrew the Republic, and caused the founding of the Roman Empire.
Conflicts with Mithridates (89–63 BC) and the Cilician pirates (67 BC)
Mithridates the Great was the ruler of Pontus a large kingdom in Asia Minor (modern Turkey), from 120 to 63 BC. Mithridates antagonised Rome by seeking to expand his kingdom,[82] and Rome for her part seemed equally eager for war and the spoils and prestige that it might bring. In 88 BC, Mithridates ordered the killing of a majority of the 80,000 Romans living in his kingdom. The massacre was the official reason given for the commencement of hostilities in the First Mithridatic War. The Roman general Lucius Cornelius Sulla forced Mithridates out of Greece proper, but then had to return to Italy to answer the internal threat posed by his rival, Gaius Marius. A peace was made between Rome and Pontus, but this proved only a temporary lull.
The Second Mithridatic War began when Rome tried to annex a province that Mithridates claimed as his own. In the Third Mithridatic War, first Lucius Licinius Lucullus and then Pompey the Great were sent against Mithridates.[85] Mithridates was finally defeated by Pompey in the night-time Battle of the Lycus.
Rome against the Cilician pirates
The Mediterranean had at this time fallen into the hands of pirates largely from Cilicia. The pirates not only strangled shipping lanes but also plundered many cities on the coasts of Greece and Asia. Pompey was nominated as commander of a special naval task force to campaign against the pirates. It took Pompey just forty days to clear the western portion of the sea of pirates and restore communication between Iberia (Spain), Africa, and Italy.
Caesar's early campaigns (59–50 BC)
Gallic Wars
During his term as praetor in the Iberian Peninsula (modern Portugal and Spain), Pompey's contemporary Julius Caesar defeated two local tribes in battle.[88] After his term as consul in 59 BC, he was appointed to a five-year term as the proconsular Governor of Cisalpine Gaul (part of current northern Italy), Transalpine Gaul (current southern France) and Illyria (part of the modern Balkans).[88][89] Not content with an idle governorship, Caesar strove to find reason to invade Gaul (modern France and Belgium), which would give him the dramatic military success he sought. When two local tribes began to migrate on a route that would take them near (not into) the Roman province of Transalpine Gaul, Caesar had the barely sufficient excuse he needed for his Gallic Wars, fought between 58 BC and 49 BC.
Caesar defeated large armies at major battles 58 and 57 BC. In 55 and 54 BC he made two expeditions into Britain, the first Roman to do so. Caesar then defeated a union of Gauls at the Battle of Alesia completing the Roman conquest of Transalpine Gaul. By 50 BC, all of Gaul lay in Roman hands. Gaul never regained its Celtic identity, never attempted another nationalist rebellion, and, except for the Crisis of the Third Century, remained loyal to Rome until the fall of the western empire in 476.
Triumvirates and Caesarian ascension (53–30 BC)
Caesar's Civil War
By 59 BC an unofficial political alliance known as the First Triumvirate was formed between Gaius Julius Caesar, Marcus Licinius Crassus, and Gnaeus Pompeius Magnus ("Pompey the Great") to share power and influence. In 53 BC, Crassus launched a Roman invasion of the Parthian Empire (modern Iraq and Iran). After initial successes he marched his army deep into the desert; but here his army was cut off deep in enemy territory, surrounded and slaughtered at the Battle of Carrhae in which Crassus himself perished. The death of Crassus removed some of the balance in the Triumvirate and, consequently, Caesar and Pompey began to move apart. While Caesar was fighting in Gaul, Pompey proceeded with a legislative agenda for Rome that revealed that he was at best ambivalent towards Caesar and perhaps now covertly allied with Caesar's political enemies. In 51 BC, some Roman senators demanded that Caesar not be permitted to stand for consul unless he turned over control of his armies to the state, which would have left Caesar defenceless before his enemies. Caesar chose civil war over laying down his command and facing trial.
By the spring of 49 BC, the hardened legions of Caesar crossed the river Rubicon, the legal boundary of Roman Italy beyond which no commander might bring his army, and swept down the Italian peninsula towards Rome, while Pompey ordered the abandonment of Rome. Afterwards Caesar turned his attention to the Pompeian stronghold of Hispania (modern Spain) but decided to tackle Pompey himself in Greece. Pompey initially defeated Caesar, but failed to follow up on the victory, and was decisively defeated at the Battle of Pharsalus in 48 BC despite outnumbering Caesar's forces two to one, albeit with inferior quality troops. Pompey fled again, this time to Egypt, where he was murdered.
Pompey's death did not end the civil war, as Caesar's many enemies fought on. In 46 BC Caesar lost perhaps as much as a third of his army, but ultimately came back to defeat the Pompeian army of Metellus Scipio in the Battle of Thapsus, after which the Pompeians retreated yet again to Hispania. Caesar then defeated the combined Pompeian forces at the Battle of Munda.
Caesar was now the primary figure of the Roman state, enforcing and entrenching his powers. His enemies feared that he had ambitions to become an autocratic ruler. Arguing that the Roman Republic was in danger, a group of senators hatched a conspiracy and assassinated Caesar at a meeting of the Senate in March 44 BC. Mark Antony, Caesar's lieutenant, condemned Caesar's assassination, and war broke out between the two factions. Antony was denounced as a public enemy, and Caesar's adopted son and chosen heir, Gaius Octavianus, was entrusted with the command of the war against him. At the Battle of Mutina Mark Antony was defeated by the consuls Hirtius and Pansa, who were both killed.
Octavian came to terms with Caesarians Antony and Lepidus in 43 BC when the Second Triumvirate was formed. In 42 BC Mark Antony and Octavian fought the Battle of Philippi against Caesar's assassins Brutus and Cassius. Although Brutus defeated Octavian, Antony defeated Cassius, who committed suicide. Brutus did likewise soon afterwards.
However, civil war flared again when the Second Triumvirate of Octavian, Lepidus and Mark Antony failed. The ambitious Octavian built a power base of patronage and then launched a campaign against Mark Antony.[99] At the naval Battle of Actium off the coast of Greece, Octavian decisively defeated Antony and Cleopatra. Octavian was granted a series of special powers including sole "imperium" within the city of Rome, permanent consular powers and credit for every Roman military victory, since all future generals were assumed to be acting under his command. In 27 BC Octavian was granted the use of the names "Augustus" and "Princeps", indicating his primary status above all other Romans, and he adopted the title "Imperator Caesar" making him the first Roman Emperor.