This paper highlights some roles architectural history can uniquely play bothvis-à-vispolitical history and/or in constructing it. Through looking at a particular city – Lyons – it suggests how the disregard both of built evidenceper seand of its specifically architectural interpretation has distorted the conventional account of that city's history. By means of a particular case study, of perhaps the most significant single building within that city – its town hall – it indicates some of the ways in which architectural history can serve to enrich political history, and indeed why it should be considered an essential tool for such history.