Occitan is a language derived from Latin, imposed by the Romand after the conquest of Gaul. For this reason, it is now classified as a Gaul-Roman language or Romance.
Dante Alighieri in 14th century attempted an early classification of romance spoken and took as a reference the particle related to the statement thus determining three idioms: the language of “yes”, Italian, the language of “Oil”, French, and the language of “òc”, Occitan. From the latter term will then spread that of Occitania to indicate the places in the south of France where the Occitan is spoken.
The oldest European literary document written in a Romance language is in Occitan and dates to 880. But it is from the 12th century that the most glorious period of Occitan literature begins in Aquitaine, through the development of troubadour poetry, which will continue throughout the 13th century, lapping not only the south of France, but the whole southern Europe.
The troubadours become the inspiration of the main poetic schools of Europe from the Sicilian to the German, up to Dante and Dolce Stil Novo. In fact, Dante will recognize a debt to this lyric, so much so that in Divine Comedy, in Canto XXVI of Purgatory, he will insert the figure of Arnout Daniel, a troubadour who declares some verses in Occitan:

Tan m'abellis vostre cortes deman,
qu’ieu no me puesc ni voill a vos cobrire.
Ieu sui Arnaut, que plor e vau cantan;
consiros vei la passada folor,
e vei jausen lo joi qu'esper, denan.
Ara vos prec, per aquella valor
que vos guida al som de l'escalina,
sovenha vos a temps de ma dolor!

(“delighted me so much, that I can not,
nor do I wish to, hide myself from you.
Arnaut am I, who, going, weep and sing;
with sorrow my past folly I behold,
and see with joy the hoped-for coming day.
Now by the Power which guides you to the top
of this short flight of stairs, I beg of you
be mindful in due time of this my pain!”)

Occitan thus proves to be a language of considerable importance for the time, in fact it will be the only one, with Latin, to make its appearance in the Divine Comedy.
In the South of France, in 1539, with the edict of Viller- Cotterês, Kinf Francis I officially banned the òc language from use in the public administration, relegating it in this way only to popular language.
In the following centuries there will be cases of revival of this language also from a literary point of view, but it will only be in the 19th century that there will be a real resurgence thanks to the birth of “Felibrige”, a literary movement founded in 1854, with the aim of defending and enhancing the Occitan language in all its variants. This will be done mainly thanks to the poetics of Frédéric Mistral, its founder, who will compose in the Provencal version a series of poems, including “Mirèio”, and in 1904 he will receive the Nobel Prize in Literature.
In the 20th century with the foundation of I.E.O., the Institut d’Etudis Occitans, is embarking on a new phase of protection and dissemination of the language.
Occitan is now present in three states (France, Spain, Italy) in the following areas: the south of France, with 32 departments with a population of 12 million, Spain, with the Val d’Aran with 7 thousand inhabitants; Italy, with 10 valleys and about 90 thousand inhabitants. The Piedmont Guard in Calabria is also Occitan.
Occitan is divided into two large “families” with different pronunciations and characteristics: that of south-Occitan and that of north-Occitan. These in turn are still divided into several local variants: for south-Occitan the Gascon, the Languedoc and the Provence; for the north-Occitan the “Limosino”, the “Alverniate” and the “Vivaro-Alpino”. Part of the latter are the spoken of the Occitan valleys of Italy, and therefore also of the Stura Valley.  
The Vivaro-Alpino has differences from the other variants: the palatization of consonants –c and g- turning into –ch and –j, the total fall of the final –t in past male participles, the verbal ending of the first person in –o, the frequent rhotacism of –l and the maintenance of the final –r in the infinitives.
In the field of writing two were the main schools that originated graphs spread throughout the Occitan territory. In 1854 Felibrige’s literary movement elaborated a phonetic handwriting using the French. From this model the handwriting “Escolo dou Po” will then be elaborated in the Piedmont valleys. In 1935 Lois Alibert published the Occitan Grammar and an Occitan French dictionary in which he proposed a handwriting adapted to the classical one of the troubadours called “etymological”.