We investigate the relationship between land dispossessions of peasants and the origin of the civil conflict in Colombia. Using a matching-pair instrumental variable approach, we show that the historical dispossession of peasants' lands by landlords that led to the rise of peasant grievances is associated with the activity of the rural guerrilla movement -Revolutionary Forces of Colombia (FARC) - during the first stage of the Colombian civil conflict ( 1964-1985). We exploit the random variation in floods to identify the effect of peasants' land dispossessions during 1914-1946 on the rise of rural guerrilla movements. Using a novel municipal-level data set, the study documents that municipalities experiencing floods b etween 1914 and 1946 were substantially more likely to experience land dispossession than municipalities that did not. Floods temporarily worsened the conditions of the land and its value, facilitating the dispossession of peasant land by large landowners. We propose two mechanisms through which previous land dispossession resulted in the emergence of rebel-armed groups. On the one hand, the ideological cohesion stemming from radical liberals and communists exacerbated the grievances and helped to shape the political objectives of the rebel armed groups. On the other hand, exposure to prior violent events gave military training, access to weapons, and military experience to the rural population, that likely emboldened the formation of rebel groups.
