These are fascinating Romance dialects spoken in Sicily. The are called the Gallo-Italic dialects of Sicily. Some of them are also found in other parts of Italy, mostly in the far south in Basilicata.
Gallo-Italic languages are spoken in far north of Italy and are so called because there is heavy French influence on these Italian varieties. They include Venetian, East and West Lombard, Piedmontese, Ligurian, Emilian and Romagnolo.
In the 1100′s and 1200′s, Sicily was ruled by Norman rulers from the north of France. They had conquered much of Italy, and were in control of parts of the north also. In order perhaps to consolidate their rule in Sicily, which they had just conquered, they sent some Norman soldiers to Sicily to help populate the region and set up Norman outposts there.
These were mostly soldiers from the southern Piedmont (Monferrate) and Ligurian (Oltregiogo) regions of Italy and from the Provencal area in the south of France. There were also a few from the Lombard region and other parts of northern Italy. They went down there with their families and formed a number of settlements in Sicily and a few other places in Italy.
Over the next 800 years, their Gallo-Italic language came under heavy influence of varieties of Sicilian in Sicily, Basilicatan in Basilicata and other languages in other parts of Italy. Yet the heavy Gallo-Italic nature of their lects remains to this day and Sicilian speakers of surrounding villages find Gallo-Italic speakers impossible to understand.
The dialects have tended to die out somewhat in the past 100 years. Villagers were tired of speaking a language that could not be understood outside the village and increasingly shifted to the Sicilian language. A situation of bilingualism in Gallo-Italic and Sicilian developed. Over time, this became trilingualism as children learned Standard Italian in school. Gallo-Italic was used inside the village itself, and Sicilian was used for communication with outsiders.
Whether or not Gallo-Italic lects in different parts of Sicily can understand each other is not known, but they have all undergone independent paths of development over 800 years or so. The same is also an up in the air question about Basilicatan Gallo-Italic and Gallo-Italic settlements in other parts of the country. This is an interesting question in need of linguistic research.
In this 1 1/2 minute video, I am not sure if I understood a single word he said. The language he is speaking sounds like a mixture of Provencal Piedmontese with a heavy dose of Sicilian. Sicilian itself is so odd that a Sicilian speaker can barely be understood at all outside of Sicily. It has at least 250,000 words, 25% of which have no equivalent in Standard Italian. It underwent heavy French, Spanish and especially Greek and Arabic influences.