What is the effect of political violence on electoral support for anti-system parties? We argue that the effect of violence is asymmetric and predominantly benefits nationalist, radical-right parties. Posing as defenders of the nation, nationalist parties benefit from violence by their political opponents and violence targeted against perceived threats to the nation. To test this conjecture, we collect novel actor-based and geospatial data of political violence in interwar Italy. Using a difference-in-differences estimator, we model the effect of violence on vote shares of anti-system parties at the municipality-level in the 1919 and 1921 elections. Our results indicate increasing electoral support for the nationalist Fascist party in municipalities that experienced violence committed by either the far right or left after the 1919 election. In contrast, the leftist Socialist party loses electoral support if violence occurs. We conclude by discussing the relevance of our finding for increasing violence in liberal democracies today.