Early literary sources seldom agree on the origins of gladiators and the gladiator games. In the late 1st century BC, Nicolaus of Damascus believed they were Etruscan. A generation later, Livy wrote that they were first held in 310 BC by the Campanians in celebration of their victory over the Samnites. Long after the games had ceased, the 7th century AD writer Isidore of Seville derived Latin lanista (manager of gladiators) from the Etruscan word for "executioner," and the title of Charon (an official who accompanied the dead from the Roman gladiatorial arena) from Charun, psychopomp of the Etruscan underworld. This was accepted and repeated in most early modern, standard histories of the games.
Reappraisal of pictorial evidence supports a Campanian origin, or at least a borrowing, for the games and gladiators. Campania hosted the earliest known gladiator schools (ludi). Tomb frescoes from the Campanian city of Paestum (4th century BC) show paired fighters, with helmets, spears and shields, in a propitiatory funeral blood-rite that anticipates early Roman gladiator games. Compared to these images, supporting evidence from Etruscan tomb-paintings is tentative and late. The Paestum frescoes may represent the continuation of a much older tradition, acquired or inherited from Greek colonists of the 8th century BC.
Livy places the first Roman gladiator games (264 BC) in the early stage of Rome's First Punic War against Carthage, when Decimus Iunius Brutus Scaeva had three gladiator pairs fight to the death in Rome's "cattle market" Forum (Forum Boarium) to honor his dead father, Brutus Pera. This is described as a munus (plural: munera), a commemorative duty owed the manes of a dead ancestor by his descendants. The development of the munus and its gladiator types was most strongly influenced by Samnium's support for Hannibal and the subsequent punitive expeditions against the Samnites by Rome and her Campanian allies; the earliest and most frequently mentioned type was the Samnite.
The war in Samnium, immediately afterwards, was attended with equal danger and an equally glorious conclusion. The enemy, besides their other warlike preparation, had made their battle-line to glitter with new and splendid arms. There were two corps: the shields of the one were inlaid with gold, of the other with silver ... The Romans had already heard of these splendid accoutrements, but their generals had taught them that a soldier should be rough to look on, not adorned with gold and silver but putting his trust in iron and in courage ... The Dictator, as decreed by the senate, celebrated a triumph, in which by far the finest show was afforded by the captured armour. So the Romans made use of the splendid armour of their enemies to do honour to their gods; while the Campanians, in consequence of their pride and in hatred of the Samnites, equipped after this fashion the gladiators who furnished them entertainment at their feasts, and bestowed on them the name Samnites. (Livy 9.40)
Livy's account skirts the funereal, sacrificial function of early Roman gladiator combats and reflects the later theatrical ethos of the Roman gladiator show: splendidly, exotically armed and armoured barbarians, treacherous and degenerate, are dominated by Roman iron and native courage. His plain Romans virtuously dedicate the magnificent spoils of war to the Gods. Their Campanian allies stage a dinner entertainment using gladiators who may not be Samnites, but play the Samnite role. Other groups and tribes would join the cast list as Roman territories expanded. Most gladiators were armed and armoured in the manner of the enemies of Rome. The munus became a morally instructive form of historic enactment in which the only honourable option for the gladiator was to fight well, or else die well.
In 216 BC, Marcus Aemilius Lepidus, late consul and augur, was honoured by his sons with three days of gladiatora munera in the Forum Romanum, using twenty-two pairs of gladiators. Ten years later, Scipio Africanus gave a commemorative munus in Iberia for his father and uncle, casualties in the Punic Wars. High status non-Romans, and possibly Romans too, volunteered as his gladiators. The context of the Punic Wars and Rome's near-disastrous defeat at the Battle of Cannae (216 BC) link these early games to munificence, the celebration of military victory and the religious expiation of military disaster; these munera appear to serve a morale-raising agenda in an era of military threat and expansion. The next recorded munus, held for the funeral of Publius Licinius in 183 BC, was more extravagant. It involved three days of funeral games, 120 gladiators, and public distribution of meat (visceratio data) – a practice that reflected the gladiatorial fights at Campanian banquets described by Livy and later deplored by Silius Italicus.
The enthusiastic adoption of gladiatoria munera by Rome's Iberian allies shows how easily, and how early, the culture of the gladiator munus permeated places far from Rome itself. By 174 BC, "small" Roman munera (private or public), provided by an editor of relatively low importance, may have been so commonplace and unremarkable they were not considered worth recording:
Many gladiatorial games were given in that year, some unimportant, one noteworthy beyond the rest — that of Titus Flamininus which he gave to commemorate the death of his father, which lasted four days, and was accompanied by a public distribution of meats, a banquet, and scenic performances. The climax of the show which was big for the time was that in three days seventy four gladiators fought.
In 105 BC, the ruling consuls offered Rome its first taste of state-sponsored "barbarian combat" demonstrated by gladiators from Capua, as part of a training program for the military. It proved immensely popular. Thereafter, the gladiator contests formerly restricted to private munera were often included in the state games (ludi) that accompanied the major religious festivals. Where traditional ludi had been dedicated to a deity, such as Jupiter, the munera could be dedicated to an aristocratic sponsor's divine or heroic ancestor.
Gladiator games offered their sponsors extravagantly expensive but effective opportunities for self-promotion, and gave their clients and potential voters exciting entertainment at little or no cost to themselves. Gladiators became big business for trainers and owners, for politicians on the make and those who had reached the top and wished to stay there. A politically ambitious privatus (private citizen) might postpone his deceased father's munus to the election season, when a generous show might drum up votes; those in power and those seeking it needed the support of the plebeians and their tribunes, whose votes might be won with the mere promise of an exceptionally good show. Sulla, during his term as praetor, showed his usual acumen in breaking his own sumptuary laws to give the most lavish munus yet seen in Rome, on occasion of his wife's funeral.
In the closing years of the politically and socially unstable Late Republic, any aristocratic owner of gladiators had political muscle at his disposal. In 65 BC, newly elected curule aedile Julius Caesar held games that he justified as munus to his father, who had been dead for 20 years. Despite an already enormous personal debt, he used 320 gladiator pairs in silvered armour. He had more available in Capua but the Senate, mindful of the recent Spartacus revolt and fearful of Caesar's burgeoning private armies and rising popularity, imposed a limit of 320 pairs as the maximum number of gladiators any citizen could keep in Rome. Caesar's showmanship was unprecedented in scale and expense; he had staged a munus as memorial rather than funeral rite, eroding any practical or meaningful distinction between munus and ludi.
Gladiatorial games, usually linked with beast shows, spread throughout the Republic and beyond. Anti-corruption laws of 65 and 63 BC attempted but failed to curb the political usefulness of the games to their sponsors. Following Caesar's assassination and the Roman Civil War, Augustus assumed Imperial authority over the games, including munera, and formalised their provision as a civic and religious duty. His revision of sumptuary law capped private and public expenditure on munera, claiming to save the Roman elite from the bankruptcies they would otherwise suffer, and restricted their performance to the festivals of Saturnalia and Quinquatria. Henceforth, the ceiling cost for a praetor's "economical" official munus employing a maximum 120 gladiators was to be 25,000 denarii; a "generous" Imperial ludi might cost no less than 180,000 denarii. Throughout the Empire, the greatest and most celebrated games would now be identified with the state-sponsored Imperial cult, which furthered public recognition, respect and approval for the Emperor's divine numen, his laws, and his agents. Between 108 and 109 AD, Trajan celebrated his Dacian victories using a reported 10,000 gladiators and 11,000 animals over 123 days. The cost of gladiators and munera continued to spiral out of control. Legislation of 177 AD by Marcus Aurelius did little to stop it, and was completely ignored by his son, Commodus.