Successful constitutionalism is characterized by de jure Constitutional provisions de facto binding political agents. A growing literature seeks to quantify cross-country variation in Constitutional compliance and explore its determinants (e.g., Law and Versteeg in Calif Law Rev 101(C):863-952, 2013; Gutmann et al. in University of Hamburg, Institute of Law and Economics Working Paper 2022 No. 57, 2022; Voigt in Int J Const Law 19(5):1778-1809, 2021). We explore long-institutional memories of representative assemblies as a determinant. We employ Bologna Pavlik and Young's (Econ Gov 21(2):133-186, 2020, South Econ J 88(1):414-448, 2021) measure of medieval/Early Modern assembly experiences. Assembly experiences are positively associated with Constitutional compliance. However, breaking them down into tax veto and spending prerogative experiences, the former is positively related to compliance; the latter is negatively related.