By the fifth century Latin had become the language of education and been brought to new areas via the expansion of Christianity. The grammars by Donatus (fourth century) and Priscian’s (sixth century) were the canonical textbooks.The Carolingian Renaissance (eighth-ninth century) had linguistic consequences: promotion of scholarship, return to original texts, reform of pronunciation. The twelfth century represents a turning point in the study of language: the aim is not just describing Latin and practical training, but reflecting on the relationship between ‘dialectic’ (logic) and grammar (cf. Peter Helias). This opened the way to a general/formal theory of language, ‘speculative grammar.’ It flourished in the thirteenth century, with the idea that language intervenes both in the knowledge of reality and the theory of the ‘modes of signifying.' The Modistae systematized their predecessors’ work and investigated further the relation of grammar and meaning and the universal properties of language. In the fifteenth century the nominalists, for whom the modes of signifying were unnecessary, attacked their theories.The author notes an interest in pragmatics coming from theologians, rather than grammarians and philosophers. The chapter closes on a review of grammars of vernaculars (Catalan, Provençal, Old French).