This paper presents intergenerational evidence in favor of the hypothesis
that a signi…cant factor explaining the increase in female labor force
participation over time was the growing presence of men who grew up with
a di¤erent family model–one in which their mother worked. We use di¤erences
in mobilization rates of men across states during WWII as a source of
exogenous variation in female labor supply. We show, in particular, that
higher WWII male mobilization rates led to a higher fraction of women
working not only for the generation directly a¤ected by the war, but also
for the next generation. These women were young enough to pro…t from
the changed composition in the pool of men (i.e., from the fact that WWII
created more men with mothers who worked). We also show that states in
which the ratio of the average fertility of working relative to non-working
women is greatest, have higher female labor supply twenty years later.