<<Leonese can also be considered a language because it's not Spanish, just another Romance tongue (very close to Spanish but distinct). But as it never had a writen form because Leonese speakers were extremely diglossic, it remained as let's say "dialect". >>
You are wrong:
<<Leonese derives directly from language and took shape in the early Middle Ages. At that time, Leonese was the official language of the Leonese Kingdom and achieved a high codification grade [9]. Leonese developed a proper codification in the territories of the actual provinces of Llión, Zamora and Salamanca and in the Leonese territories in the actual Portugal, especially in the District of Braganza. So, the local laws called "Fueros" are mainly written in Leonese, and the documentation from the monasteries in this land is also in Leonese.
[edit] Middle Ages
The first written text in Leonese is the Nodicia de Kesos (959 or 974); other works in the language include Fueru de Llión, Fueru de Salamanca, Fueru Xulgu, Códice d'Alfonsu XI, ou Disputa d'Elena y María[10] or Llibru d'Alixandre[11].
[edit] Modern Era
The Modern Era signifies a new opportunity for Leonese to show that big writers could also use it for writing important pieces. Writers like Torres Naharro, Juan del Encina, Lucas Fernández or Torres Villarroel in the Modern Era cultivated Leonese, which however came on the verge of disappearance during the XIXth century.
[edit] 19th and 20th centuries: International research
International philologues of the XIXth century, like Gessner, Hanssen, Staaff or Menéndez Pidal, in Europe and America, started to describe Leonese. Some writers like Caitano Bardón (Cuentos en Dialecto Leonés), Luis Maldonado or Aragón Escacena (Entre brumas) restarted the Leonese literature in the early XXth century.
[edit] Contemporary Leonese
Cuentos del Sil book's coverThere is a new generation of writers in Leonese, especially in urban areas, that are developing new creations. One of the best examples is "Cuentos del Sil", a Leonese language book promoted by Leonese language associations El Fueyu and El Toralín who had the support of Leonese Provincial Government. There are nine writers, from teenagers to old people, but most of them under their forties, that developed stories in Leonese. All the writers had a relationship with the lands where the Sil river runs.
The situation of Leonese as a minority language has driven Leonese to near extinction and is considered a seriously endangered language by the UNESCO [12]. There are some efforts to gain acceptance among the urban population, (the Leonese Council and other municipalities such as Zamora, Coyanza, Mansilla de las Mulas or La Bañeza made campaigns in and for teaching Leonese). Leonese language associations and some administrations are now promoting its knowledge and use, especially Llión City Council where it is widely used in their internet communications.
[edit] Internet presence
Internet was a new field for promoting and developing Leonese, where Leonese grammar is being fixed.[13] The main reason is that Leonese has seen more publications in Internet in the last year than books were edited. In this sense, Leonese has seen great progress in being permitted the creation of associations like puntuLLI, for requesting a Top Level Domain for the Leonese language and culture[14].>>
http://en.wikipedia.org/wiki/Leonese_language