We document the short- and long-run effects of male-biased sex ratios. We exploit a natural historical experiment where large numbers of male convicts and far fewer female convicts were sent to Australia in the 18th and 19th centuries. In areas with more male-biased sex ratios, women were historically more likely to get married and less likely to work outside the home. In these areas today, both men and women continue to have more conservative attitudes towards women working, and women work fewer hours outside the home. While these women enjoy more leisure, they are also less likely to work in high-ranking occupations. We demonstrate that the consequences of uneven sex ratios on cultural attitudes, labor supply decisions, and occupational choices can persist in the long run, well after sex ratios are back to the natural rate. We document the roles of vertical cultural transmission and marriage homogamy in sustaining this cultural persistence.