Recent studies have analyzed the way in which the absence of well-defined property rights can generate the conditions for violent outbreaks to emerge.However, there are few studies that analyze the way in which violence, in the long run, can affect the structure of property rights in the regions that are affected.In this paper I investigate the effect of violence in the rates of informality in the possession of land in Colombia in the long run.By studying one of the periods of most intense violence in Colombia in the 20 th century I find evidence that the municipalities affected during this period have informality rates in the possession of land which are higher in close to 2.9 percentage points (0.15 standard deviations).