This is a personal delineation of part of a methodology for the History of the French Language, aiming to combine the methodology of linguistics with that of history proper. Both traditional and modern methods of ‘historical linguistics’ fail to take account of a real time dimension, whereas ‘language history’ often resembles institutional, cultural and social history. We ask how we identify the ‘event’ and the ‘object’ of linguistic history, and how we distinguish variation, innovation, shift and change. We ask also what the linguist can contribute to the historian's reconstruction of the past.