Hoang-Anh Ho, Peter Martinsson & Ola Olsson. The Origins of Cultural Divergence. EfD Discussion Paper Series DP 19-08
Cultural norms diverge substantially across societies, often within the same country. In the present paper, we propose and investigate the selective migration hypothesis, proposing that cultural differences along the individualism collectivism dimension are driven by the out-migration of individualistic people from collectivist societies to frontier areas, and that such patterns of historical migration are reflected even in the current distribution of cultural norms. Gaining independence in 939 after 1000 years of Chinese colonization, historical Vietnam occupied the region that is now north Vietnam with a collectivist social organization. From the 11th to the 18th centuries, historical Vietnam. gradually expanded its territory southward to the Mekong River Delta through various waves of conquest and migration. Combining findings from a household survey and a lab-in-the-field experiment, we demonstrate that areas annexed earlier to historical Vietnam are currently more prone to a collectivist culture. Relying on many historical accounts, together with various robustness checks, we show that the southward out-migration of individualistic people during the territorial expansion is an important driver behind this finding.