The comparison between parliaments and theatre has often been used to criticize the superficial show that hides the real societal issues politics should be concerned about. In this contribution, the comparison between theatre and parliaments is a heuristic tool to show that parliaments really offer a certain form of theatre. The contribution concentrates on the use of theatrical metaphors in and around nineteenth-century British and French parliaments, that were then seen as the most important parliaments and certainly as the most important parliamentary ‘stages’. The ‘theatrical’ side of parliaments shows the ambiguity as well as the crucial importance of their public nature. Parliaments were seen as providing serious, uplifting theatre but also vulgar theatricality. The serious Burkean theatre and its counterparts in the French Restoration and July monarchy or the sober Netherlands parliament provided the framework for good discussions: a strict separation of participants and audience, respect for rules and traditions of debate, exchange of arguments more or less according to the classic unities of tragedy. However, the Burkean conception of moral theatre risked having the elitist effect of excluding a public not versed in its rules, or whose main concerns were not addressed in the ongoing debates. That is why elements of demotic or popular theatricality have helped to democratize parliaments, make them more accessible to the public at large and mobilize the constituency by offering them clear choices between issues and protagonists. The function of the debates could be better understood by analysing them as theatre plays with crucial roles for the main actors and the public.