Abstract This project proposes an innovative approach to the history of French by replacing the ‘tunnel vision’ (Watts/Trudgill 2002) which characterizes the vast majority of studies of ‘Classical French’ by a wider approach, based on an extraordinarily valuable source, i.e. the ‘Prize Papers’. The Prize Papers are a collection which includes 50,000 undelivered private French letters, confiscated between 1652 and 1815 during the frequent military conflicts between France and England. The documents are held by the National Archives of the United Kingdom in London, and are remnants of the privateering era, a longstanding legitimate activity of capturing enemy ships. These countless captured letters are becoming known to historians, who have recognized them as an invaluable source of information on the period in question, but have so far attracted little attention from linguists, even those focusing on diachrony. The MACINTOSH project is the first French initiative to explore this collection, and aims to show how the alternative data provided by these private documents can broaden the scope and fill the gaps left by traditional historical linguistics. The research focuses on the first French colonial era, shedding new light on the dynamics and mechanisms that led to the French and Creole varieties existing in America and the Indian Ocean.