This paper focuses on the structural damage assessment of the Doria Malaspina Castle, a historic masonry building located in Calice al Cornoviglio, Italy. The castle exhibits various cracking patterns, prompting an investigation to determine their causes. To address this, advanced numerical simulations were integrated with historical research, damage surveys, and 3D laser scanning. Historical records were initially combined with recent crack surveys to identify potential damage sources. A detailed geometric model of the entire castle was then developed based on a 3D laser scanner survey. This model served as the basis for creating a three-dimensional finite element model, which allowed for the simulation of different actions identified as possible causes of damage. The numerical model successfully replicated both past and current crack patterns, offering valuable insights into the factors responsible for the observed damage.