The Mirandese language (mirandés or lhéngua mirandesa; mirandês or língua mirandesa) is an Astur-Leonese language or language variety that is sparsely spoken in a small area of northeastern Portugal in Terra de Miranda (made up of the municipalities of Miranda do Douro, Mogadouro and Vimioso). The Assembly of the Republic granted it official recognition alongside Portuguese for local matters on 17 September 1998 with the law 7/99 of 29 January 1999. In 2001, Mirandese was officially recognised by the European Bureau for Lesser-Used Languages, which aims to promote the survival of the least spoken European languages.
Mirandese has a distinct phonology, morphology and syntax. It has its roots in the local Vulgar Latin spoken in the northern Iberian Peninsula.
Mirandese is a descendant of the Astur-Leonese variety spoken in the Kingdom of León and has both archaisms and innovations that differentiate it from the modern varieties of Astur-Leonese spoken in Spain. In recognition of these differences, and due to its political isolation from the rest of the Astur-Leonese speaking territory, Mirandese has adopted a different written norm to the one used in Spain for Astur-Leonese.
In the 19th century, José Leite de Vasconcelos described Mirandese as "the language of the farms, of work, home, and love between the Mirandese". Since 1986–87, it has been taught optionally to students at the primary and lower secondary level, and has thus been somewhat recovering. By Law 7/99, Mirandese was given official recognition by the Assembly of the Republic alongside Portuguese. The law provides for its promotion and allows its usage for local matters in Miranda do Douro.
Today Mirandese retains fewer than 5,000 speakers (but the number can be up to 15,000 if counting second-language speakers) in the villages of the Municipality of Miranda do Douro and in some eastern villages (such as Vilar Seco and Angueira); in Caçarelhos, it is considered recently extinct of the Municipality of Vimioso, and some linguistic influence can be observed at other villages of the municipality of Vimioso and the municipalities of Mogadouro, Macedo de Cavaleiros and Bragança.