In 1886 important archeologicals find were discovered of a necropolis Volscan. This find showing  that Isola del Liri was inhabited by this population. Citizenship, then, tried to resist the domination of the Roman Empire flanking, along with nearby Arpinum, the Samnite army. The struggle for independence did not have a good end, in fact the two cities had to bow to Roman rule in 305 B.C, A jump in the story leads us up to 1010 d. C. when the gestaldo Sora and Arpino, Peter the First Rachis, ceded this territory to the jurisdiction of his children. Island, during this period, reached its total independence because it disuniting itself from Arpino. A weakening of the 'economy of the city were the constant battles like the battle between Pope Innocent III and Emperor Frederick II, his godson, the struggle that ended with the destruction of the city. The history of the island is intended to be once again  victim of violence, like that which between the Aragonese and Angevin that, after a series of complex historical events, induced the family Boncompagni to buy the Duchy of Sora in 1580. For the citizens began a period of comfort, art and culture flourished, but the breath was short because in 1796 the territory passed to Royal government property in Naples and, an era of terror followed this period. Tha last years of the eighteenth century there were the consequences of the French Revolution and sad effects of banditry.Positive was the intuition of Joachim Murat on the exploitation of the Fibreno’s energy power. This energy power used as a driving force for the industries of paper that became more numerous. The economic wealth improved the quality of life of the citizens, so Isola Del Liri was called "Little Paris". At the end of the nineteenth century the future of the companies became uncertain, many of them tried to resist but, in the '70s, the non-industrial modernization, brought an end to the activity of many companies in the area.