Introduction: Emile Durkheim differentiated between two types of wars: National and Civil Wars in terms of effect on suicide mortality. This study investigates Durkheim’s assertion by examining the effect of Irish Civil War on the 1882-1928 suicide rates trend. Method: The study is based on vital statistics data sourced from Central Statistics Office of Ireland. We used AutoRegressive Integrated Moving Average with Explanatory variables (ARIMAX) design adopting Bayesian approach. Results: The Standardized Mortality Rate SMR for death by suicide for the total Irish population during the civil war period were reduced by 0.041417 (95% Credible Interval CI: -0.2421749 to 0.15934012). The SMR for death by suicide for the total Irish population during the First World War period were reduced by 0.206202 (95% CI: -0.3776463 to -0.03475746). Conclusion: Evidence from this study support a significant drop in terms of the intensity of suicidal behaviour in the Irish population during World War I more so than during the Irish Civil War.