Having repelled the invasions by the Celtic Gauls, Rome again set its sight on expansion.  They reconquered those Latium and Etruscan towns that sought to elude the Gallic chaos by escaping from the Roman Republic’s Alliance.  Rome re-consolidated its position of the dominant force in Latium and central Italy. They looked south toward Campania (where on the Map?).  By this time, the Samnites had moved into the fertile lands of Campania.  They controlled the towns of Copus and Cumae to the south of Rome.  Conflicts with Samnitium for Campanian dominance were inevitable leading to a series of three wars of 50 years duration. 
The 1st Samnite war began when Neapolis (Naples) called upon Rome to help them in their struggles against repeated invasions by the warlike Samnites.  It was brief and resulted in some significant victories for Rome.  However, strikes and revolts by its Latium allies because they had not been conscripted to fight outside their own country,  required Rome to breakoff its military operations and suppress  the Latiums.  The conflicts resulted in major acquisitions of the rich lands of Campania with its capital Capua.  The Campanians saw that they were no match for the aggressive Samnites and an alliance with Rome was necessary.  The political strategy of the Romans was that a well-structured alliance, safe-guarding certain rights to both parties, would lead to the successful and beneficial absorption of Campania within the Roman Republic.  These alliances brought wealth and territory to the Roman Republic and also boosted her already ample manpower for future legionary campaigns.
In the 2nd Samnite war 323 BC (approx), The Roman Republic increased its influence in Southern Italy by taking the city-state Magna Cracia (Greek).  B y the end of the 2nd war, military occupation enabled Rome to establish many new colonies and control over central and southern Italy. 
The 3rd Samnite war  (end: 290 BC – 50 Years of War   This last war was on its largest scale as the Samnites were joined by Gauls including King Bennus and the Umbrians, the Sabines, the Aegui and the Volsci.  The Rome victory here  consolidated its position as Master of central Italy.