Cato the Younger

He also started to adopt an ostentatious pattern of public antiquarianism. To that end, he adopted an austere lifestyle where he refused to travel long distances on horseback (preferring to walk), travelled the city barefoot, and wore only a toga without a tunic.[17] His sartorial choices were modelled on statues of Rome's legendary founders and heroes, who were depicted wearing togas alone, rather than any philosophical inclinations.[18] His choices were deliberate and political:

He was raised in a wealthy aristocratic house that is not known to have departed from mainstream contemporary culture... He made a deliberate decision to break with the norms of his peers... faced [with] daunting challenges in his intended political career[,] he leveraged his strongest asset – his great-grandfather's reputation as a champion of tradition – to enhance his own status.

By adopting the archaic style of dress found on statues of Rome’s ancient heroes, he sought to present himself as the ideal of Roman virtue. This presentation of tradition was sure to appeal to the conservative senators... but there was also a strong popular appeal in Cato’s unique behaviour.[19]

The basilica Porcia was a small building to the left of the curia Hostilia (in red) in the Roman Forum raised by Cato's great-grandfather. It was Rome's first basilica; it burnt down in 52 BC.[20]

His first appearance on the public stage was to oppose changes to the Basilica Porcia, a public building commissioned by his great-grandfather Cato the Elder during his term as censor in 184 BC.[21] The plebeian tribunes proposed moving a column that impeded their view of the Forum. Cato may have been expected to defend the monument – "public buildings such as the Basilica Porcia were prized heirlooms that perpetuated a family's fame and greatness, so men could be expected to defend their family monuments"[21] – but the column may not have actually been part of the Basilica. Regardless, Cato used the opportunity to enter public life with an appearance defending his family's honour and reputation, showing his pietas, and connecting himself to his famous ancestor.[22]

Cato's first marriage was early in his twenties. He was first betrothed to his cousin Aemilia Lepida (and daughter of Mamercus Lepidus). The reasons were unclear: because of his close relations to Mamercus Lepidus, the match would not have been very useful politically in building new alliances; he may have been motivated by love or by the large size of the dowry.[22] Aemilia Lepida had previously been betrothed to Quintus Caecilius Metellus Pius Scipio Nasica, but Scipio broke off the match, after which Cato was betrothed. However, some time later, Scipio changed his mind and Lepidus evidently decided that a match with Scipio was more desirable. The two were married shortly after. Cato was angry and threatened a lawsuit against his uncle to enforce his engagement, but was dissuaded by his friends.[23]

He instead married Atilia, the daughter of an Atilius Serranus (the specific identity is unknown). While the gens Atilia had consular ancestors, it had not been successful in reaching the consulship after the end of the second century BC.[24] By her, he later had a son, Marcus Porcius Cato, and a daughter, Porcia.[25] Around this time he also secured an excellent marriage for his sister in Lucius Domitius Ahenobarbus.[26] His half-sisters' very favourable matches helped develop a strong network of political allies.[27]

In 72 BC, Cato volunteered to fight in the war against Spartacus, presumably to support his half-brother Caepio, who was serving as a military tribune in the consular army of Lucius Gellius.[27] Although the army was defeated twice in battle, Cato's valour was recognised. Although the consul Gellius recommended Cato for awards, he publicly declined them and "advertised that his standard for military accomplishment were much more stringent than the consul's, and the strangeness of this act was so shocking that it was talked about and remembered back in Rome".[28]

A few years later, in 67 BC, he stood for the military tribunate.[29] After winning election, he was dispatched to Macedonia under propraetor Marcus Rubrius, where he earned the respect of the soldiers by sharing their burdens and treating them justly. He also maintained his "unusual habit of walking everywhere instead of riding a horse".[30] Over a winter, he travelled to Pergamum and became the patron of a Greek Stoic philosopher named Athenodorus, contradicting Cato the Elder's "famous position against Greek philosophers", who accompanied Cato back to Rome.[31]

During his service in Macedonia, he received the news that his beloved half-brother Caepio was ill and dying in Thrace. He immediately went to see him but was unable to arrive before his brother's death. Cato was overwhelmed by grief and, ignoring Stoic principles of apatheia (living without passions), he spared no expense to organise lavish funeral ceremonies.[32] After the end of his military commission, he travelled through Asia Minor and through Galatia "in such a quiet and unassuming way that he was often mistaken for a man of low status".[33] Before returning to Rome, he also visited Pompey, who was then supervising the final stages of the Third Mithridatic War. Cato, according to Plutarch, received an exaggerated and deferential welcome from the proconsul, which most scholars doubt actually occurred.[34]

Cato was assigned to the state treasury (the aerarium) in Rome as one of the urban quaestors. The complexity of Roman financial law and the treasury's record-keeping had led to Roman aristocrats "abdicating their supervisory roles to the professional clerks who worked in the treasury" and resulted in widespread corruption.[39] Cato started his term by prosecuting a number of the clerks and firing a number of others; even after one was acquitted after intervention from one of the censors, Cato refused to rehire him.[40][41]

He also started the process of collecting on long-standing state debts and made prompt payments to state creditors.[42] In doing so, he cooperated with Julius Caesar, who had then just completed a term as curule aedile and was acting as a prosecutor in court, in challenging the legal immunity and payments given to men who had received bounties for killings during the Sullan proscriptions.[43] He also changed procedures to ensure that the treasury archives rejected fraudulent documents.[39]

On his last day in the aerarium, Plutarch reports that he discovered that his old friend and colleague in the urban quaestorship, Marcus Claudius Marcellus, was entering fraudulent records; Cato apparently stormed back to erase them before the end of his term. He also spent an enormous amount of money – some five talents, about four per cent of his inheritance - to make copies of all the treasury archives from Sulla to his own day "to facilitate the prosecution of future wrongdoers" that might succeed him in the aerarium.[44]

Cato's reputation in the aerarium was exemplary. According to Plutarch's biography, he "taught men that a city can be rich without treating its citizens unjustly" and "brought the quaestorship into greater esteem than the senate, so that everybody thought and said that Cato had given the quaestorship the dignity of the consulship".[42]

Propaganda cup of Cato (the cup to the left, the one to the right being dedicated to Catiline), for his canvass for the plebeian tribunate of 62 BC. These cups, filled with food or drinks, were distributed in the streets to the people, and bore an inscription supporting the candidate to the election.

An 1889 depiction by Cesare Maccari of Cicero, then consul, speaking against Catiline, at right.

In 63 BC, Cato stood for the plebeian tribunate of 62 BC.[45] After his election but before his term started in December, he opposed granting additional honours to Pompey, engaged in an unsuccessful prosecution of Lucius Licinius Murena, and was part of in a famous debate on the Catilinarian conspiracy.[3]

Lucius Sergius Catilina, a noble patrician, led a rebellion against the state, raising an army in Etruria. Upon discovery of an associated plot against the lives of the consuls and other magistrates in Rome, Cicero arrested the conspirators within the city and proposed executing them without trial, a violation of citizen rights to appeal. While Cicero could have done this on his own authority (augmented by a senatus consultum ultimum), he convened the senate, almost certainly to diffuse responsibility.[46] The matter of killing the conspirators was a novel one: while the use of deadly force against citizens under arms was generally accepted, "the disposal of captured and unarmed conspirators was a more difficult matter".[47]

Cato's brother-in-law, Decimus Junius Silanus, who was one of the consuls-elect, spoke first in favour of death, as did the rest of the former consuls. But Julius Caesar, then praetor-elect, countered with a proposal to imprison the conspirators, which started to gain the support of the house.[48] Cato spoke two or three speeches after Caesar. According to Sallust, among other things he argued that the senate was being too soft against enemies of the state, that it was folly to await the ultimate test of the conspirators' guilt – the overthrow of the state – because the very proof of their guilt would make it impossible to enforce the law, and that precedent and religious scruples demanded severe action.[49] In Sallust's depiction, both Cato and Caesar make appeals to precedent and mos maiorum: Caesar calls executing the subdued conspirators "a new type of punishment" and attempted to draw Cato into contradicting his great-grandfather's lenient stance on the Rhodians after the Third Macedonian War; Cato viewed executing traitors as consistent with ancient Roman tradition.[50] While Caesar's speech – due to the fact he was praetor-elect and would soon assume office – seemed to come with "an unspoken threat... of prosecution under a hostile judge", Cato's counter-arguments "stiffened [the senators'] resolve [and excited] their fears that they may not even live to see the next year if they did not take the hardest line possible".[51]

Cato and his political allies also saw in the Catilinarian crisis an opportunity to ruin Caesar's career, if not have him killed, by falsely incriminating him as being a part of the conspiracy. The famous story of Cato's misinterpreting a love letter from Servilia (Cato's half-sister and wife of consul-elect Silanus) to Caesar as incriminating evidence comes from this episode and "highlights how desperate Cato was to destroy Caesar".[52] The source of the enmity was both political and personal: historians speculate various reasons, from political opposition to envy of Caesar's social and political success (by this time he had already been elected pontifex maximus, beating out a family ally,) to retaliation for malicious rumours of Caesar's having been Cato's nephew's father or that Caesar was purchasing sexual favours from his Servilia's daughter.[53] At the same time, it is easy to see contemporary parallels between Caesar and Catiline: Caesar had likely supported Catiline's bids for the consulship; Caesar, like Catiline, was buried under massive debts; Caesar too hailed from an ancient patrician clan that had fallen on hard times; and Caesar too would have been forced into exile or bankrupt obscurity if he were to fail in his political career.[54]

Ruins of the Temple of Castor and Pollux in the Roman Forum. The ruins visible today date to the time of Tiberius.

Cato's first action on entering his tribunate in December 63 BC was to propose a law expanding the grain dole.[55] He brought the bill with the support of the senate late in the year, according to Plutarch, to calm discontent in the city and strengthen the senate's political position.[56] The law more than doubled the number of people receiving subsidised grain, placed a considerable burden on the republic's finances, and possibly made Cato one of the most generous politicians in the history of the grain dole.[57] His grain bill also showed that the lex frumentaria was not the exclusive preserve of the so-called "populares",[58] but rather, that "the advocacy of corn distribution knew no party".[59]

One of the other tribunes of the plebs, Metellus Nepos, proposed two bills to grant Pompey additional honours. The first would transfer command of the (nearly completed) campaign against Catiline in northern Italy to Pompey. The second would have allowed Pompey to stand in absentia for the consulship of 61 BC and to lead troops into the pomerium (the sacred boundary of the city).[60] Cato strongly opposed both.[61] When Nepos initially presented the bill, Cato tried to talk him down as a friend but was unsuccessful, returning to invective after Nepos refused.[62] The senate, at Cato's urging, voted down the bills; Nepos therefore moved to bring them before the popular assemblies regardless.[63]

Nepos, along with his ally Caesar, assembled the assembly at the Forum before the Temple of Castor and Pollux. Cato and one of his allies, another tribune named Quintus Minucius Thermus, forced their way to the front and Cato then "brusquely took a seat between Nepos and Caesar [to prevent] them from communicating privately".[63] When Nepos directed the bill to be read, he vetoed it; when Nepos started to read it himself, Cato snatched the draft from his hands; when Nepos started to recite it from memory, Thermus put his hand over the Nepos' mouth to stop him from speaking.[64] A fight accordingly broke out in the Forum.[64] In response to the mob violence, the senate passed a senatus consultum ultimum;[65] Nepos fled Rome to Pompey in the east and Caesar backed down.[66] Suetonius and Plutarch then assert that Nepos, Caesar, or both were removed from their offices; modern scholars do not believe these assertions, as the senate during the republic had no such powers.[67] More contemporaneous sources imply that the senate may have moved to ratify Nepos' departure from the city (tribunes were legally forbidden from leaving the city), which Cato likely objected to.[68]

Later, Cato, with another fellow tribune named Lucius Marius, passed a law establishing penalties for military commanders who misrepresented the number of enemies or Roman soldiers killed in battles and required commanders to swear as to the accuracy of the numbers in their reports when returning from campaign.[69] The law may have been aimed at Caesar, who would take up in the following year a governorship in Spain, where he would have opportunities to campaign against the Spanish tribes.[70] Cato may also have been involved in the passage of a law requiring candidates at elections to make their official declarations of candidacy in person before an official within the city; such a law precluded a general from holding a military command and standing for office, as entering the pomerium vitiated promagisterial imperium (military command authority).[71] This law may have been aimed at Pompey, who was thought to desire another consulship on his return, or Caesar, to force him to choose between the consulship and military glory.[72]

Near the end of 62 BC, a scandal occurred involving Publius Clodius Pulcher's sacrilegious intrusion into secret rites to Bona Dea. When Clodius was acquitted on charges of sacrilege, apparently due to jury tampering via bribery, Cato moved to correct a loophole in the law.[73] While the lex Aurelia in 70 BC had distributed the jury pool between senators, equestrians, and the tribuni aerarii,[74] the anti-graft provisions of then-existing laws applied only to senators, meaning that bribing the non-senatorial jurors was legal. Cato's push against bribery was opposed by some of his normal allies, such as Cicero, who believed that it undermined senatorial government in alienating the equestrians.[75]

Cato was fortunate to emerge into politics during a "changing of the guard" in the senate. The previous Social War, followed by Sulla's civil war and then the proscriptions, had destroyed a great number of senatorial families.[76] Because of the great bloodletting of previous decades and a growing trend toward semi-retirement rather than active political life after leaving office, by 65 BC, the number of senior leaders – consulares, that is, former consuls – in the senate had fallen to just nine.[77] Cato's pro-senatorial beliefs and oratorical skills positioned him in taking an active role in opposing those "men who[,] in his view[,] threatened the conventional order of the senate":[78]

Since the optimates were not a political party, Cato was not joining a specific group of senators linked by a particular social or political outlook, but was claiming a prominent place among those who championed the traditional conduct of politics and the senate's claim to lead the state.[78]

Moreover, his archaic mannerisms also helped him gain influence among the senators and the people: by making "himself into a living example of the old-fashioned Roman... [he] tapped into the deep vein of patriotism and conservatism that ran through the blood of every Roman citizen... disagreeing with [Cato] seemed to be a rejection of Roman tradition and therefore of Rome itself".[79] His antiquarianism and birth to a family that had produced consuls more than a century into the past also helped win prestige among the senatorial elite, "who believed that their right to govern Rome was in large part inherited".[80]

For Fred Drogula, Cato's posturing as "the voice of the ancestors enabled him to push or shame others into agreeing with his opinions", which also helped to make up for his meagre financial resources in an expensive political environment where large bribes paid to voters was a normal part of campaigning.[81] His policies also symbolised "for the aristocracy a nobility of purpose and principle that they liked to associate with their whole order".[82] It, however, made him a difficult ally or potential ally whose "extreme interpretation of conservatism gave him little room to compromise without seeming to abandon his principles".[83]

By the end of his tribunate, he was very popular among the nobility: "such influence was remarkable for a man who had not yet reached the praetorship or commanded an army".[84] He also was instrumental in uniting the senate, even at this earlier time, against Caesar; his success in his anti-Caesarian politics, however, forced Caesar "look elsewhere to achieve political success" and thereby forced Caesar to adopt more aggressive popularis tactics.[85]

In the years after his tribunate, many of the other leading conservative senators died or retired. Cato then assumed a loose leadership of the more conservative wing of senators.[86]

Caesar's consular year started with his bringing, in the normal manner, a bill before the senate to distribute public lands to poor citizens and Pompey's veterans.[103] Well written, brought in the traditional manner, and deferential to the senate's prerogatives, Cato lacked any real justification to oppose it; he settled instead for filibustering.[104] For the whole of January, he prevented the senate from acting on the bill and was dragged to prison at Caesar's orders before being released.[105] Caesar moved instead to bring the matter before the people.[106]

Bibulus, called to a public debate on the bill, offered no substantive reasons for opposition before exclaiming, in frustration, "You will not have this law this year, not even should you all want it!"[106] Thereafter, Cato and Bibulus moved to declare unfavourable religious omens every morning to preclude a vote, until one morning they were assaulted in the street and driven off, pelted with manure.[107][108] Added to Caesar's bill was the requirement that senators swear to uphold the law or face punishment; Cato and an ally refused, until Cicero gave a face-saving argument that "Rome was better served by Cato's presence than by his absence", leading them to take the oath on the last day before the deadline.[109]

With a sufficient portion of the public on Caesar's side after Bibulus' embarrassing display of obstinate obstructionism and his Bibulus' self-confinement to his home, Caesar moved rapidly to pass further legislation. Over the first half of the year, he passed laws:

• recognising Ptolemy XII Auletes as Egyptian king,
• ratifying Pompey's eastern settlements,
• bailing out the publicani tax farmers for Crassus, and
• adding Campania to his lex agraria.[109]

Cato and his allies continued to resist these bills, but were unsuccessful.[110] Plutarch reports Cato was again dragged to prison for his opposition, but "it is likely that Plutarch has duplicated the story... for heroic effect".[111] He also opposed the lex Vatinia which assigned to Caesar the provinces of Cisalpine Gaul and Illyricum for five years.[112][113] Alone, he also opposed Caesar's assignment to Transalpine Gaul as well. Cato and his allies may also have engaged in a boycott of public business to cast doubt on the legitimacy of Caesar's acts.[112]

Cato, however, supported one bill Caesar brought forth, the lex Iulia de repetundis, which detailed specific financial and administrative duties for governors to prevent extortion and embezzlement by provincial governors.[114] His opposition to Caesar's legislative programme was likely focused only on those bills which would benefit Caesar personally, which – unlike passing land reform laws – suppressing corruption would not do.[115]

Throughout the consulship, Cato and his allies also produced a substantive amount of propaganda meant to discredit Caesar and his triumviral allies by branding them tyrants, a message reinforced by the violence visited upon Bibulus to secure passage of the agrarian law; the campaign was successful in making it difficult for the three allies to use political violence out of fear that they might validate their opposition's rumours.[116] The senators cowed into assent to Caesar's policies started to filter out of Caesar's camp, though "not necessarily joining Cato's group", leading to another reshuffling of alliances.[117]

Following Caesar's consulship and departure to Gaul, opponents of Caesar started to move to question the legal validity of his legislative actions.[118] They also brought Publius Vatinius, the tribune who had passed the lex Vatinia assigning the provinces to Caesar, to stand charges, but the court proceedings were disrupted by a mob led by Publius Clodius Pulcher.[119]

Pulcher had been elected during Caesar's consulship as one of the plebeian tribunes of 58 BC. Also in office were a number of triumvirate-friendly magistrates, including both consuls.[120] In March of that year, Clodius promulgated a bill annexing the island of Cyprus. The assignment of governor was initially slated for one of the consuls – Aulus Gabinius, a friend of Pompey, – but after he was unable to take the post, Clodius promulgated a bill to appoint Cato instead as pro quaestore pro praetore.[121][122] Reasons for the appointment are divided: the traditional view is that Clodius wanted Cato away on business;[123][124] other historians have suggested that doing so was instead an attempt to forge a political alliance or that Cato gave away Cicero's exile for the appointment.[125] Accounts of public reactions to the appointment also were divided: Cicero, for example, praised Cato for accepting it, as, even though Cicero rejected the annexation, he believed Cato to be the right person for the job; on the other hand, Plutarch reports that Cato was forced by law to go.[126] Modern historians also see another reason: there was little productive to do in Rome when triumviral allies controlled all the major magistracies; leaving for Cyprus would allow Cato to buttress his reputation as an honest governor while waiting for the political winds to shift.[127]

After arriving in Cyprus and announcing annexation, the local king – a Roman ally – there killed himself rather than suffer the indignity of deposition. Cato then "undertook every aspect of the cataloguing and appraisals [of the royal possessions] himself... and spoke with each prospective buyer to encourage them to bid on items".[128] In doing so, he demonstrated great diligence, but alienated some of his friends in the meantime, receiving them poorly and treating them with suspicion.[129] Cato's loss of his account books, low amount recovered from Cyprus, and over-preparation on his return to Rome could indicate that he engaged in some modest embezzlements or allowed his nephew, Marcus Junius Brutus, to engage in usurious moneylending or embezzlement on his behalf.[130] His administration of Cyprus, was, however, well regarded on his reputation for honesty alone.[131] Upon his return, he held, a de facto glittering naval parade up the Tiber before starting a procession conveying the treasures to the treasury.[132]

By the time Cato returned from Cyprus, Cicero had been recalled from exile with Pompey's support (after Clodius had turned on Pompey).[133] Cicero's gratitude and debt to Pompey had him support Pompey's ambitions: shortly after his return, Cicero proposed a prestigious and wide-ranging grain commission and proposed extraordinarily long supplicationes for Caesar's Gallic victories.[133] Cato also divorced his loving wife Marcia so he could – with her father – marry her to his friend, Quintus Hortensius, in part to cement an alliance.[134]

By 56 BC, the triumviral coalition was "in a shambles".[135] With Pompey attacked both by the conservative Cato-aligned senators and by Clodius – who was himself an independent operator[136] – Pompey was forced to double down in his alliance with the other triumvirs. Added was the threat of Caesar's replacement in Gaul, setting up the renewal of the triumviral coalition at the Luca Conference: Caesar would, for Pompey, bring Clodius to heel, both Pompey and Crassus would receive prestigious military commands following a dual consulship, and Caesar would be renewed in Gaul.[137] Without the ability to win elections outright, the three allies decided on chaos: "by desperate postponement of the elections into the following year... an interregnum would weaken the leadership of the opposition... [allowing] Crassus and Pompey to hope for more favourable results".[138]

At untimely elections marred by mob violence, Cato supported Lucius Domitius Ahenobarbus, his brother-in-law.[139] After the triumvirs distributed bribes and used force to force the other candidates from the elections, Pompey and Crassus were elected consuls for 55 BC in late January the same year.[138][140] At those elections, Cato stood for the praetorship against Publius Vatinius; he secured support among the initial voters, so Pompey interrupted the elections to give more bribes and remove known Catonian voters. Vatinius was then elected.[141]

At the debate that year about the lex Trebonia to grant Crassus the province of Syria so he could fight a war of choice against the Parthian Empire, Cato again repeated his tactic of speaking until his opponents had him arrested so he could claim to be poorly treated. To avoid the a repeat of this embarrassment, at later debates, his attendance was barred by armed mobs.[142] He tried similar obstructive tactics against the lex Licinia Pompeia to extend Caesar's command, but again failed. At this time, Plutarch reports – if not an injection of imaginative foreshadowing – that Cato started to change his tact to split Pompey from Caesar by warning Pompey of Caesar's ambitions.[143]

Pompey and Crassus' consulship, while a short-term success, was unsuccessful in the long-run.[138] The elections for the magistrates for 54 BC were a victory for Cato and his allies. Without violence to force a decision, the electorate reacted coldly to the triumvirs' favoured candidates.[144] Lucius Domitius Ahenobarbus – who had stood the previous year – and Appius Claudius Pulcher were elected.[145] Cato was returned for a praetorship and allotted the presidency of the extortion court.[146] Opponents of the triumvirs immediately brought a number of prosecutions against the triumvirs' allies, but almost all were acquitted "in large part because the complex network of connections among senators meant that the litigants could not be reduced to stark choices between two political parties or ideologies".[147]

One case was that against Aulus Gabinius, who was convicted for receiving a ten thousand talent bribe to invade Egypt to place Ptolemy XII Auletes back on the throne. He was forced to go into exile. Of the many prosecutions brought against triumviral supporters, Gabinius' was the only one successful.[148] Cato may also have "ben[t] the laws" to expand the jurisdiction of his corruption court with the goal of furthering "anti-bribery reforms that he had thus far failed to advance".[149]

Cato also brought legislation to clamp down on electoral bribery by requiring that all candidates submit detailed financial records. But the bill, although passed by the senate, was unpopular among the people and defeated: "the citizens on the whole profited from the large annual disbursements of cash by wealthy senators, and they no doubt wanted those payments to continue".[150] Similarly unpopular was Cato's reaction to Caesar's victories over the Gauls and Germans: on receipt of reports that Caesar had attacked during a truce but won a victory in which he killed some 430 thousand Germans, "Cato alone expressed anger at the victory[;] he considered Caesar's actions to be a gross violation of 'international law'... [and] urged that Caesar be handed over to the survivors of the massacre in atonement".[151]

That year also proved that Cato's push for stronger anti-bribery legislation both been a failure and was deeply needed. As interest rates doubled as candidates borrowed to finance bribes, a deal was struck between the two conservative sitting consuls, a triumviral supporter, and a triumviral opponent to pool resources to bribe voters and support the sitting consuls' assignment to desirable provinces. When one of the participants disclosed the plot to the senate, all were charged with electoral corruption, with the largest loss falling on the consul Domitius (Cato's brother-in-law).[152] In response to the scandal, the senate delayed elections for an inquiry, but tribunes started to bring vetoes against various electoral proposals.[153]

Repeated tribunician vetoes prevented elections to be held in 54 for the magistrates for 53 BC. The ancient sources believe that the delays were artificially created to justify the creation of Pompey as dictator, calls which Cato and senators such as Brutus,[154] strongly opposed.[155] After Cato praised Pompey on his civic-mindedness in publicly refusing a possible dictatorship, he "seems to have created a momentary period of stability" which led to the election of two conservative consuls, Gnaeus Domitius Calvinus and Marcus Valerius Messalla Rufus in July 53 BC.[156] During their truncated terms, they seem only to have tried to pass one bill, to introduce a delay between magistracy and governorship of five years: doing so reduced the ability for consuls to select their own provinces and made it more difficult to borrow money, to be repaid from provincial earnings, by delaying those provincial earnings.[157] Cato was probably one of the co-authors and major supporters of the proposal; it was, however, defeated before the people and panned by younger senators.[158]

While Caesar's daughter, Julia, had died the previous year, Pompey's support of Caesar continued: he lent a legion from Spain to Gaul at Caesar's request (a deal Cato condemned for bypassing the senate).[159] Also in 53, news arrived of Crassus' defeat and death at the hands of the Parthians in Syria. While Plutarch reports this made a confrontation between Caesar and Pompey inevitable, their alliance did not immediately break down, even after Pompey's marriage to Cornelia Metella.[160][161]

The year also was rocked with political violence between the duelling mobs led by Clodius and Titus Annius Milo, who also was standing for the consulship. Their months-long clashes, along with tribunician obstruction against the holding of elections, led again to calls for Pompey as dictator.[162] After the year started with no magistrates and Clodius was murdered by Milo after a chance encounter, the level of violence increased; among other things, the senate house and the Basilica Porcia in the Forum was destroyed by fire as Clodius' makeshift funeral pyre.[163][164]

With a political impasse and anarchy in the streets, Cato and Bibulus proposed making Pompey sole consul (ie consul without a colleague). Plutarch and others report that this was to deny Pompey a dictatorship while also establishing a functioning government.[165] Some modern historians, such as John T Ramsey, however, conceive of the choice in political terms: the obstructive tribunes wanted to prosecute Milo for Clodius' murder, which could not happen if he were elected to the consulship and gained legal immunity. Electing Pompey alone would stabilise the city and, by precluding Milo's election, ensure Milo could be brought to trial.[166][167] While a clear departure from tradition, it allowed Pompey to be brought on side while also restoring order to the city without handing Pompey unlimited power.[168]

Pompey's sole consulship was a turning point in the republic.[169] He convened a trial, with jurors intimidated by his soldiers, in which Milo was condemned for public disorder. Cato was possibly involved as a quaesitor, which may have been part of the compromise to bring Milo to trial.[170] However, Cato had not succeeded in bringing Pompey fully into the senatorial fold: Pompey during his consulship supported the so-called "law of the ten tribunes" which granted Caesar the right to stand for the consulship in absentia.[171]

With starting success in forcing a break between Pompey and Caesar, Cato stood for the consulship of 51 BC. He reportedly did so out of a claim of public duty, in the vein of Lucius Quinctius Cincinnatus being summoned by the people, to defend the republic from Caesar and Pompey.[172] He was defeated after running a campaign in which he "distribute[d] no cash and promise[d] no favours; the campaign seem[ed] to have been designed to win admiration rather than votes".[173] Cicero complained that while the state needed him, Cato was unwilling or unable to put aside his "vision of the mos maiorum to do what was necessary to win an election"; regardless, after his defeat, Cato did not stand for the consulship again.[174]

Cato was surprised that Caesar had actually crossed the Rubicon. While "Cato and his supporters had worked tenaciously to push Caesar into a corner where his only choices were civil war and political ruin... Cato seems to have been surprised and depressed by the consequences of his political strategy... he would soon be found saying that peace was worth making concessions".[190] When news of Caesar's rapid advance south reached Rome, Pompey made the decision to flee Italy for the eastern provinces and to use the fleet to contain Caesar to Italy before retaking the peninsula.[191]

When Caesar offered peace terms on 23 January that he would be willing to lay down his command and stand for a consulship in person in return for amnesty and Pompey's departure to Spain, Cicero relates that Cato strongly supported the plan and forced himself into the war council at which the proposal was discussed.[192] That the peace offers were decisively rejected by the hard-liners who wanted to defeat Caesar militarily indicates that Cato by this point had lost control of his coalition.[193] He attempted to have the senate give Pompey overall command, but the senate chose to divide command among various generals, who Caesar then defeated in detail.[194]

Pompey assigned Cato to Sicily to raise men and supplies. This decision "may have been more political than military... Cato's gloomy attitude toward civil war... [would make him] too far away to interfere with the bloody business of the legions".[195] Another reconstruction, however, places Cato at the centre of an abortive strategy to blockade Italy to starve Caesar out by stripping Italy of Sicilian grain supplies.[196] But on 23 April, after being faced with a landing by Gaius Asinius Pollio, he abandoned the island – apparently, according to Cicero, without giving battle, even though his forces were sufficient to hold the island.[197] Regardless, after further Caesarian landings under Curio, Cato would have been forced to retreat.[198]

After retreating, Cato fled to join Pompey at Dyrrhachium.[198] Upon his arrival there, Plutarch relates that Cato admitted that Cicero's more moderate policy, advocating compromise with Caesar, had been "more useful to his country": "[Cato's] distress at the consequences of his own hard-line policies... may have been weigh heavily on him".[199] He was then sent to Asia Minor to organise transport ships; but finding no need for himself, he induced Rhodes to take Pompey's side and left his family there before returning to Pompey in Greece, where he declined command of naval forces, citing Bibulus' senior consular claim.[200] After the indecisive Pompeian victory at the Battle of Dyrrhachium, Cato is said to have "wailed loudly for his country... [and] lamented the destructive and miserable lust for power" after seeing the casualties.[201]

Cato was not present at the Battle of Pharsalus. He had opposed the proposals that Pompey should chase Caesar down after his withdrawal from Dyrrhachium.[202] Left in command of that port, also possibly for political reasons to remove critics (including Cicero) from decision-making following a prospective Pompeian victory, Cato received news of the defeat from Titus Labienus.[203] In the aftermath of the defeat, he decamped to Corcyra and asked Cicero to take command because he still held imperium from his promagistracy and was the senior consular present; Cicero declined, preferring instead to return home and seek Caesar's pardon.[204] Allowing defectors to leave peacefully, Cato loaded his men and set sail for Egypt via Cyrene.[205] But learning of Pompey's death at the hands of the Ptolemies and that Quintus Caecilius Metellus Pius Scipio was still in command in Africa, he moved to join them.[175] Discovering a fractured situation, he reconciled Metellus Scipio with Publius Attius Varus and had Metellus Scipio put in command.[206] While the recorded reasons were that Cato believed that Metellus Scipio had both consular dignity and a name that would inspire the soldiers, as the inheritor of the Cornelii Scipiones that had defeated Hannibal, "[Cato] probably had no stomach for fighting against his countrymen".[206]

Cato's "politics of constant obstruction and provocation" also made compromise "significantly harder to achieve" while also being "at variance with everything that was most traditional about the republic... it was a dangerous political stance that prevented both him and others from addressing the actual problems Rome faced and from finding solutions that could have created a more stable and less contested republic".[218] The traditional political culture of the middle republic was one built around aristocratic compromise, political debate, and reform.[219] Yet, Cato's obstructive tactics "where unconventional and even radical [in] trying to block senatorial consensus rather than promote it".[104] His policies with regard to stopping powerful politicians such as Pompey, Caesar, and Crassus alienated – through its very success – them from the rest of the senatorial class, leading to the formation of the alliance between their alliance.[220]

Many scholars believe that Cato's political strategy before 49 BC contributed significantly in starting the civil war that was the proximate cause of the collapse of the Roman republic, even if he did not intend for conflict.[221][222][223][224][225] While his strategy – convincing senators that Caesar was a threat to the republic and wanted to make himself king – was "a great success", that success in convincing other members of the senate backfired: "the men who assumed the leading roles in opposing Caesar.... were willing to go to any length to destroy [him], even if that meant a civil war".[177]

During most of his political career, he "steadfastly pursued" the "frustration of powerful military figures... by the unparalleled exploitation of all the obstructive tactics available".[221] This uncompromising position had him push strongly, before the civil war, for further confrontation with Caesar, seemingly to pressure Caesar to back down.[226] Cato and his allies also pushed Pompey away from the various olive branches and compromises before the civil war. Up to the last, when Pompey was close to accepting an offer where Caesar would give up all his legions except one and provinces except Illyricum, Cato chastised Pompey for "allowing himself to be deceived 'again'".[227] To the extent that Caesar may have feared prosecution, conviction, and exile – a "dubious" claim[228][229][230] – Cato was one of the few pushing strongly for Caesar's political destruction via prosecution.[189]

After his death, his "rivalry [with Caesar] came to be seen as a conflict of ideologies... Cato increasingly came to be seen as a hero of the republic... [with his] life and death [becoming] symbols of the dying republic".[231] His life was also appropriated by Augustus as a symbol of republican values.[232]

Modern scholars note that "the 'Stoic martyr' tradition has distorted or distracted from the historical Cato".[233] The extent of his belief in Stoicism is debated.

Some scholars point to how Cato acted in ways profoundly inconsistent with Stoic tenets: his anger at the breaking of his betrothal to Aemilia Lepida, breakdown over the death of his half-brother Caepio, his visible despair at the sight of casualties from the civil wars, etc.[234] For such scholars, Cato's actions fit into the mould of a traditional Roman acting in line with traditional Roman values rather than Stoic ones.[235]

On the other hand, others point out that Cato's contemporaries noted his Stoic behaviours and positions explicitly. Cicero lampooned it in Pro Murena, and also mentioned it in letters and contemporaneous philosophical texts.[233]

• Engaged to Aemilia Lepida, but engagement called off
• First wife, Atilia (divorced)
  • Porcia, married first to Marcus Calpurnius Bibulus, then to Marcus Junius Brutus
  • Marcus Porcius Cato, later killed in the Second Battle of Philippi
• Second (and third) wife Marcia.