In 1925, of the 22 countries that could be classified as democracies, only four —France, Belgium, Portugal and Switzerland— had yet to extend suffrage to women. France is an intriguing exception: as a co-belligerent in WWI, the country experienced the type of social upheavals most commonly associated with the extension of women's rights, most importantly a rapid increase in female labor force participation. What explains this French exception? Why did the French political elite fail to translate post-war calls for suffrage extension into policy?

Mass warfare, we argue, has implications for rights expansion only to the extent that it disrupts the pre-war political equilibrium that had kept expansion off the docket. We hypothesize that, in the French case, WWI and its the large death toll, while it under-mined the exclusionary pre-war equilibrium in the lower chamber, ended up re-enforcing it in the upper chamber, ultimately preserving the status quo. We test our argument using a unique dataset combining election returns with constituency-level military death rate matched to pre- and post-war data on elected officials' position on women's suffrage.

This study makes at least two contributions. First, it documents how the Third Republic’s political institutions, combined with WWI death toll, ultimately delayed the extension of suffrage to women. Second, it contributes to debates about the role of conflict in shaping women’s social position. We argue that, in the case of rights expansion, imbalanced gender ratios resulting from mass warfare can hinder reform when women are viewed as undermining the electoral interests of veto players. We discuss implications for research on war and rights extension more generally.