The Great Depression coincided with the last big reversal of globalisation. What was the role of trade in making the crisis global, i.e. what were the costs of losing the gains from trade? Exploiting pre-crisis trade patterns and the varying degree of the Great Depression in major industrial countries, this paper provides a new causal estimate of the elasticity of income with respect to trade. Equipped with this elasticity, I show that the breakdown in trade can explain large parts of the crisis in many countries and some may have escaped the Depression altogether in its absence.