Constituting a central historical link between war and long-term fiscal capacity, war taxes are generally perceived to be a thing of the past. This article corrects the picture by presenting new, global data on war taxes, 68 in total, introduced between 1960 and 2020. Far from having been abandoned, war taxes have remained a crucial war-time fiscal instrument, leaving long-term imprints on tax systems across the contemporary world. Serving the twin imperatives of revenue maximisation and generation of taxpayer consent, I argue that the use of war taxes is conditioned by the relative intensity and the perceived legitimacy of a war, be it civil or inter-state. The proposed logic aligns with case evidence, further supported by macro-quantitative analysis. The results speak to the large literature on war and state-building, challenge the standard disintegrative view of civil wars, and provide new empirical insights into the political economy of conflict-affected countries.