In the time between the Samnite and Social Wars, a few Samnite cities acquired the “quality and dignity” of municipi.Masciotta A municipium was a self governing community of non-Roman origin, annexed by Rome. Not sovereign, they kept their cultural identity, laws, religion, language and customs. But few had full rights as Roman citizens. Pasquinucci

"Even Larinum, a town much more likely to produce criminals than consuls, got two of its sons into the [Roman consulship] before Samnium did.” Salmon 393
In testament to its role as a hub, the city used three alphabets at the same time: Oscan, Greek and Latin. Colabella
A bronze tablet found near Larino, dated 19 AD, prohibited members of the upper class from publically performing on the arena stage.

Sepino's Bovianum Gate faces the city of Bojano.
Keystone shows Hercules, god of power. Statues of Barbarian prisoners in chains warn enemies of the power of the Roman Empire. The gate exits to the tratturo (cattle track), served as customs barrier. Claudius Tiberius Nero and Drusus Germanicus, adoptive sons of Emperor Augustus, financed the walls and gate with their own money.
See Nero in Roman Who's Who
Dedicated to pagan gods, the Basilica was a multifuncional center where the elite discussed politics, economics and social problems. There are watering troughs on one side.
An inscription admonished magistrates to protect the flock owners and drivers that passed through the town each year from the rudeness and ill conduct of soldiers and inhabitants. It cited 2 letters to Rome complaining of abuses, such as falsely arresting shepherds to confiscate their cattle.
The Fullonica at Sepino dates to the Samnite period, used to card and tan sheep wool for clothing. Materials from a Samnite house, which included decorations with rhombus and swastika patterns.
Bojano (Roman Bovianum Undecumanorum)
Two ancient cities included the name Bovianum: Bovianum Vetus (maybe near Pietrabbondante)Masciotta and Bovianum Undecumanorum (Bojano). According to legend, this was the first Samnite settlement after Ver Sacrum. Settled by the 7th century BC, it was the capital of the Pentri Samnites. Centrally located on Via Minucia, Bovianum was a main trade center, opulent and important. Bojano still contains a tratturo within its city limits.
2:02 minute YouTube video
"Benvenuti a Bojano" by 931705
The demoralizing Samnite loss to the Romans at the Battle of Bovianum in 305 BC marked the beginning of the end of the 2nd Samnite War. Like Aesernia, Bovianum continued to support Rome against Hannibal and grew to a municipium. Livy described Bovianum as the grandest Samnite city, with a fortress to protect the inhabitants.
However, during the Social War (opens Social and Civil Wars article), Bovianum turned against Rome, even being named the Italian capital in 93 BC. Sulla retaliated with systematic genocide of the native population and destruction of the city. Strabo described it as “ruinous and deserted.” Cramer (Some polygon-block walls remain.) Between 9 and 14 AD, Augustus repopulated Bovianum with soldiers from the Voltinia tribe. While the city grew more prosperous, it never regained its splendor as a Roman colony. Masciotta
Already an ancient city with prehistoric settlement (opens Earliest Man article) and strong Pentri Samnite roots, Aesernia was a key communication hub for northern Samnium. Its fortress controlled the gap around the northern end of the Matese Mountains. Rome colonized Aesernia in 263 BC, Salmon and recommended it as a summer residence for Roman citizens. Today, visible fragments remain of the original polygon-block walls, a Roman bridge and about 1 mile of a still-functioning aqueduct. 
A Roman-built subterranean aqueduct supplied water from under the nearby little town of Miranda.
Panorama of Miranda
Although Aesernia distinguished itself by supporting Rome against Hannibal (opens 2nd Punic War article), it fell to the Italians during the Social War (opens Social and Civil Wars article), and served as a temporary headquarters for the Italic alliance. Consequently, Sulla punished it so severely it was nearly deserted. Strabo called it “a very inconsiderable place, having suffered materially in the [Social] war.”Cramer Later, Julius Caesar, Augustus and Nero each attempted to repopulate and revitalize Aesernia, but with little success—it never regained status as a colony.
Also remains a monument erected by M. Nonius Gallus of Aesernia, described by Salmon as “the last man not of the imperial family to erect a triumphal monument.” But Salmon cautions that:
Sulla’s “extermination, dispossession and pauperization had done their work. Accordingly when, in the closing decades of the first century, eminence is occasionally attained by a man from Samnium… it would be rash to regard him as Samnite in nationality and still more in sentiment.”
Larinum belonged to the Frentani but may have reorganized as a small, independent state before Roman subjugation. According to Livy, Larinum flourished as a municipium under Roman rule. Uniquely situated above the Biferno River (click to open map), it became a natural communication hub along the Adriatic. The road that led from Picenum to Apulia—along Hannibal’s Adriatic route to Apulia and Caesar’s route to Brindisi in pursuit of Pompey- and the Via Salaria from Pescara to Rome, ran through Larinum. Cramer
3:56 minute YouTube video
"Larino" by kalenews
Many structures dating from the time of Augustus remain today in Larino, including a forum from the first half of the 1st century AD and a 15,000-seat amphitheater from the second half (a bit earlier than the Colosseum in Rome).
Montagano (Roman Fagifulae)Stillwell
While there is some controversy about the location of the ancient city of Fagifulae. A likely prospect is near the modern town of Montagano. Just outside Montagano, the Abbey Santa Maria di Faifoli reflects the Roman name. The Roman proconsul Publio Decio assaulted and destroyed the city on his way to sack Bovianum. There, inscriptions from Emperor Hadrian (117-138 AD) to honor Antonino Pio, magistrate of Fagifulae, and others honoring Marcus Aurelius (171 AD) and Settimio Severo (211 AD)DeVito were uncovered. According to DeVito, today one can see the remains of an ancient Roman bridge of the Biferno near the Ristorante Las Vegas, near Montagano.
Sepino/Atilia (Roman Saepinum)

Saepinum's Porta Bojano, the Bovianum Gate
About 2 miles from modern Sepino lies Roman Saepinum. The city took its name from the early Samnite “saeptum,” or fence, to shelter livestock. Later, the Samnites built a fortress on higher ground, in defense of the wooden palisade.Tammaro
As Aesernia controlled the north, Saepinum controlled the route around the southern end of the Matese Mountains and supported a concentrated population.Salmon However, in a bloody battle of 293 BC, Roman legions led by Caius Papirius Cursor assaulted the fortress, set the city on fire, slaughtered 7,400 residents and took 3,000 prisoners. Survivors fled to nearby plains, eventually to live under Roman rule.Tammaro
Emperor Augustus divided some of the Saepinum land into “centuries,” square plots of about 710 meters in length, allotted to veterans of the Social War. Under Nero, Roman soldiers of the Voltinia tribe colonized Saepinum,Masciotta and the city eventually reached municipium status.

Columns of the Basilica at Saepinum
The colonists probably built the aqueduct and enclosed the ancient town within the boundaries of the existing walls, rendering it a fort in the Roman style. Although rebuilt as Roman, Saepinum uniquely retained vestiges of its Samnite origins. Its four gates, exact distances from each other, form a perfect square intersected at the center by two main roads, the Cardo and the Decumano. But while a typical Roman Cardo runs directly North to South, the Saepinum Cardo joins SW to NE, and the Decumano joins NW to SE, rather than the Roman East to West.Tammaro

The Fullonica
Termoli (Roman Interamna Frentanorum)
“Interamna” indicates location between rivers. Termoli, the ancient Interamna, sits between the mouth of the Biferno (Roman Tifernus) and the Trigno Rivers. “Frentanorum” indicates the city was a stronghold of the Frentani tribe of Samnites, and part of their network of seaports and naval arsenals. The May 2011 recovery of a Roman-era lead anchor off the coast of Termoli, and similar earlier discoveries, confirm Termoli as a main anchorage and transit port.

Off the coast of Termoli lie the Tremiti Islands, once known as the Isles of Diomede. According to legend, Diomede, hero of the Trojan War, is buried on the islands. Roman Emperor Augustus exiled his granddaughter Julia to the Tremiti in 9 AD for her adultery with a Roman Senator. There Julia gave birth to a child, but Augustus ordered the child be exposed to the elements to die. He also ordered that Julia never return to Rome, not even for burial. She died and was buried on the islands around 29 AD.Hare
Venafrum was extolled by classical authors (Cicero, Horace, Pliny) for its climate, water, fertile soil and thriving olive oil industry. Horace mentioned it as a “resort,” renowned for its amenities, and many Roman citizens kept summer residences there. Salmon counts Venafrum among cities ceded to Rome after the Samnite Wars, but suggests it did not become “Roman” until after the Pyrrhic War(opens Pyrrhic War article). It remained a praefectura (lower status than municipium) because it did not support Rome against Pyrrhus. Salmon
During the Social War (opens Social and Civil Wars article), the Samnite army annihilated the Roman cohorts garrisoned at Venafrum, and Sulla retaliated by razing settlements throughout the territory. Although colonized during the reign of Augustus, Venafrum did not obtain the status of municipium; it remained a “colonia.”
Today, traces of its ancient splendor remain. In the city center, one can see vestiges of the 15,000-seat amphitheater, the theater and odeon, the aqueduct that diverted the Volturno River from Rocchetta a Volturno, portions of its polygon-block walls, and several fragments and inscriptions.
Sources
Abbott, John S. C. Italy. New York: Peter Fenelon Collier, 1882.
Colabella, Michele. Binifero, Una Storia Millenaria. Milano: Tipolitografia Nuova Polistylegraf, 1999.
Cramer, the Rev John Antony, M.A., A Geographical and Historical Description of Ancient Italy, Volume II; Oxford: The Claredon Press, 1826.
Craven, the Hon. Keppel. Excursions in the Abruzzi and Northern Provinces of Naples, Volume II. London: Richard Bentley, 1838.
DeVito, Giovannino. Provvidenti: Note di Storia Antica e Contemporanea. Termoli: Tipolitografia “Adriatica” Iovine, n.d.
Hare, Augustus John Culbert. Cities of Southern Italy and Sicily. London: Smith, Elder & Co., 1883.
Masciotta, Dott. Giambattista, Il Molise dale origini ai nostril giorni, Volume 1, Napoli: Tipogafico Luigi Pierro e Figlio, 1914.
Pasquinucci, Marinella: “City-States and Roman Administration: from the Conquest of Latium to the Empire.” Università di Pisa, n.d.
Salmon, E.T., Samnium and the Samnites. Cambridge University Press, 1967.
Tammaro, Antonio with translation by Claudia Pezzente Gibson and Thom Tammaro. Searching the Disinterred City. Campobasso: Tipolitografia “San Giorgio.” 2004.