This project is set out within the research framework of the history of linguistic theories in Romance languages. More specifically, we aim to analyze the theoretical descriptions preoccupied with the conception of “grammatical aspect” in four major Romance grammatical traditions (French, Spanish, Italian and Portuguese). The grammatical category “aspect” was first identified as an independent category at the beginning of the 19th century and is considered rather young compared to the category of “tense”, for instance. Therefore, starting with the 15th century, when first Romance grammars emerged, we illustrate how ideas and concepts related to “aspect” had been conveyed before the category itself was finally established. With a comparative approach covering different traditions, we suggest that a theoretical network played a key role in the process of history of language theories.