This little town is an important producer of wheat and oil, and is also notable for the many remains of different historical periods.
It was a key center of the Frentani for its position on the borderline with Apulia, and since pre-Roman times a special worship of Mars, the war god, was here recorded. In 217 BC the Romans defeated Hannibal here. Later on it became a Roman "municipium" and its inhabitants were granted Roman citizenship, then under Augustus it was included in the Secunda Regio (Apulia). The ancient Roman town was located in the area now called Piano San Leonardo, which is an important archeological site.
Throughout the Middle Ages Larino was repeatedly sacked by the Saracens. In 1300 a devastating earthquake hit the area, and a few years later the Saracens utterly destroyed the settlement. After that, Larino was reconstructed in the present site and was ruled by a number of different feudal Lords (the Orsini, Pappacoda, Carafa, Sangro). In 1656 a terrible plague exterminated the population: many thousands of people died and the only 373 survivors decided to abandon the town, but thanks to the energy of their bishop Guseppe Catalano they came back and the population started to grow again.