Abstract | A methodology is developed to address the problem of the collective seismic vulnerability of historical cities. Our focus is the derivation of fragility curves of simple structural models that represent an ensemble of historical masonry buildings. The structural model estimates lateral strength using a Mohr-Coulomb type failure criterion applied on the cross sectional area of load-bearing walls in the building’s plan. Example data are drawn from the building population of the historical city of Xanthi, in Northeastern Greece. The seismic behavior of the simplified systems is efficiently assessed using approximate incremental dynamic analysis via static pushover. Monte Carlo simulation with latin hypercube sampling is applied to include the effect of epistemic uncertainties on the system performance. The result is a simple and efficient evaluation tool that can facilitate a comprehensive performance evaluation of groups of masonry structures in a seamless way that is consistent with current performance-based seismic assessment frameworks.