Peninsular Italy at the outbreak of the Pyrrhic War (adapted from Wikiwand, my additions in blue)

Venusia (291 BC)

The surviving fragments from Dionysius of Halicarnassus record that, in 291 BC, as the Third Samnite War approached its end, L. Postumius Megellus captured the Samnite town of Venusia:

1. “... a populous place, along with many other cities, of whose inhabitants 10,000 were killed and 6,200 surrendered their arms.  ... [Soon after], 20,000 colonists were sent out to [populate a newly-founded colony with Latin rights] ...” (‘Roman Antiquities’, 17: 5: 1-2).
   

This large influx of colonists brought the Romans into close contact with:

1. ✴the Greek city states of the region; and
   

2. ✴the Oscan-speaking tribes of Lucania, Apulia, Messapia and Bruttium.
   

In Construction 

War with the Lucani (probably 283-2 BC) 

Despite the friendly relation that the Romans had apparently established with the Lucani, an entry in the surviving summary of Livy’s now-lost Book 11 suggests that wars against them broke out in ca. 282 BC, when the Romans 

1. “... decided to support the inhabitants of Thurii against them”, (‘Periochae’, 11: 12).
   

The chronology of the war that followed has to be pieced together from our fragmentary surviving sources:

1. ✴An entry in the surviving summary of Livy’s now-lost Book 12 suggests that, in 283-1 BC:
   

2. •“... many [Roman] commanders successfully fought against [the Samnites], the Lucanians, Bruttians and Etruscans”, (‘Periochae’, 12: 4).
   

3. ✴Paulus Orosius (who probably relied of Livy) recorded that:
   

4. “... during the consulship of [P. Cornelius] Dolabella and [Cn.]Domitius [Calvinus: i.e., 283 BC], the Lucanians, Bruttians, and Samnites made an alliance with the Etruscans and Senonian Gauls, who were attempting to renew war against the Romans”, (‘History against the Pagans’, 3: 22).
   

5. ✴The entry for M’ Curius Dentatus at para. 3 in ‘De viris illustribus urbis Romae’ (a work by a now-anonymous author of the 4th century AD) identified Curius’ four triumphs as follows:
   

6. •his first, against the Samnites (known to have been in 290 BC);
   

7. •his second, against the Sabines (known also to have been in 290 BC;
   

8. •his third, an ovation following a victory over the Lucani (not recorded in any other surviving source); and
   

9. •his fourth, when he expelled Pyrrhus (see below) from Italy (known to have been in 275 BC)
   

10. Corey Brennan (referenced below, at pp. 432-7) suggested that Curius held his putative ovation following a victory over the Lucani as praetor in 283 BC, a suggestion accepted, for example, by:
    

11. •Nathan Rosenstien (referenced below, at p. 38); and
    

12. •John Rich (referenced below, a p. 218, note 104 and also in his completion of the Augustan fasti Triumphales, at entry 102, p. 248).
    

13. ✴According to Dionysius of Halicarnassus, when King Pyrhus (see below) tried to bribe C. Fabricius Luscinus, the latter retorted that he had already had enough opportunityies to make any money he needed:
    

14. “... especially when, 3 years ago, when I was serving as consul [i.e., in 282 BC], I was sent at the head of an army against the Samnites, Lucanians and Bruttians and ravaged a vast territory, defeated in many battles those who arrayed themselves against me, and took by storm and plundered many prosperous cities, from which I enriched my entire army, gave back to the private citizens the special taxes that they had paid in advance for the prosecution of the war, and turned into the treasury 400 talents after celebrating my triumph”, (‘Roman Antiquities’, 19: 16: 3).
    

Thus, although the date of Aelius’ law against Sthennius Statilius Lucanus is unclear, we might reasonably assume that:

1. ✴the Romans fought the Lucani in 283-2 BC on behalf of the people of Thurii;
   

2. ✴Curius was awarded an ovation in 283 BC for a victory over them;
   

3. ✴Fabricus ended the uprising of the Samnites, Lucanians and Bruttians in 282 BC, which led to his triumph; and
   

4. ✴as a result, the Romans succeeded in making Thurii’s (non-Greek) neighbours pay heavily for their transgressions.
   

Aftermath of the Lu

Appian recorded that, when a Roman naval commander who was sailing along the coast of Magna Graecia sailed into the Gulf of Tarentum in 281 BC, the Tarentines:

1. “... sank four of his ships and seized one of them with all on board.  They [also] accused the Thurini of preferring the Romans to the Tarentines although they were Greeks, and held them chiefly to blame for the Romans overpassing the limits.  Then they expelled the noblest citizens of Thurii, sacked the city, and dismissed the Roman garrison that was stationed there under a treaty”, (‘Samnite Wars’, 15).
   

We also know from Pliny the Elder that:

1. “The first statue that was erected at Rome at the expense of a foreigner was that of C. Aelius, the tribune of the people, who had introduced a law against Sthennius Statilius Lucanus for having twice attacked Thurii: on which account the inhabitants of that place presented Aelius with a statue and a golden crown”, (‘Natural History’, 34: 15).
   

The Tarantines’ decision to secure the service of Pyrrhus as the leader of the army with which they would take on the Romans was not random: Alexander of Epirus had played the same role in 334-2 BC, relation to a war that they had fought with their non-Greek neighbours (Samnites, Apuli Lucani and Brutti).

War with Tarentum

In an odd passage by Appian, we read that an unidentified naval commander  ‘Cornelius’:

1. “... carried out reconnaissance along the coast of Magna Graecia with ten ships with decks.  At Tarentum, ... a demagogue named Philocharis ... reminded the Tarentines of an old treaty by which the Romans had bound themselves not to sail beyond the promontory of Lacinium.  ... [At his prompting, the Tarentini] sank four of his ships and seized one of them with all on board.  They [also] accused the Thurini of preferring the Romans to the Tarentines although they were Greeks, and held them chiefly to blame for the Romans overpassing the limits.  Then they expelled the noblest citizens of Thurii, sacked the city, and dismissed the Roman garrison that was stationed there under a treaty”, (‘Samnite Wars’, 15).
   

This story also survives in a vey fragmentary by Dionysius, who then recorded that:

1. “Postumius, [usually identifie as the elderly L. Postumius Megellus],was sent as ambassador to the Tarentines.  As he was making an address to them, the Tarentines, far from listening to him, ... watched to see if he would make any slip in the finer points of the Greek language, [resorted to ridicule.  When they became] exasperated at his truculence, ... [they drove] him out of the theatre.  As the Romans were departing, one of the Tarentines standing beside the exit was a man named Philonides, ... being still full of yesterday's wine,  .... pulled up his garment ... [and] bespattered the sacred robe of the ambassador with the filth ... When laughter burst out from the whole theatre ... , Postumius [responded by saying::
   

2. ‘Laugh while you may, Tarentines!  Before long, [you will weep, ... and] you will wash out this robe with much blood.’
   

3. The Roman ambassadors ... [then] sailed away from their city”, (‘Roman Antiquities’, 19: 5).
   

Zonaras, having identified the Roman commander who had lost five of his ships as ‘Lucius Valerius’, the admiral, also described the travails of the ambassador Postumius and then recorded that:

1. “Upon the return of the envoys, the Romans ... voted that L. Aemilius [Barbula], the consul [of 281 BC], should campaign against the Tarentines.   He advanced to Tarentum and  [offered further negotiations], but they ... [decided] to invite Pyrrhus of Epirus to form and alliance, and sent to him envoys and gifts.  Aemilius, learning of this, proceeded to pillage and devastate their country.  They made sorties, but were routed, so that the Romans ravaged their country with impunity and got possession of some strongholds.  Aemilius showed much consideration for those taken prisoners and liberated some of the more influential; and the Tarentines ... [responded by appointing] Agis, who was a good friend of the Romans, as commander with full powers.  However, scarcely had he been elected when Pyrrhus. envoy, Cineas, planted himself in the pathway of negotiations.
   

Thus, the scene was set for the so-called Pyrrhic War. 

“[In 280 BCKing Pyrrhus of the Epirotes came to Italy to support the Tarentines”, (‘Periochae’, 12: 5);