The following reflections on the Galician Language Brotherhoods (lb, Irman-dades da Fala), an intellectual movement in favour of the emancipation of the substate regional language spoken in Northwest Iberia and founded in 1916, aim at contextualizing this movement on two axes. The first one is the contemporary context of linguistic thought and debates on language diversity at the beginning of the 20th century; the second one is the socio-diachronic evolution of Galician. One hundred years later, Galician has become the co-official language of a politically autonomous region. Alongside Spanish, it is the language of official usage, of education, mass media and of a broad range of written discourse traditions up to scientific prose. It is a “normalized” language in the sense that since the 1980s there is an official written standard and in the sense that it may be used for all social purposes, even if the overall prestige of Spanish is very strong and makes Galician frequently assume the role of a secondary language in a diglossic situation.