 With Guardiaregia, Sepino, Campobasso, Cusano Mutri it has been one of the centres of the brigandage of the southern massif of the Matese.In December 1863 the national guard besieged the brigands sheltered in the cave known as "Cava dei Briganti" and convinced them to go out, saving their lives in change.The promise was not kept and they were shot in the place named "Aria corta" situated behind the town building, After the unification of Italy, Pietraroja has experiment a strong emigration, especially towards the United States.