Inequality, ethnicity, and social cohesion

How do changes in socio-economic inequality between ethnic groups affect interethnic ties in a divided society? I analyse the evolution of cross-ethnic marriages in a society affected by violence along ethnic boundaries and make three principal findings. First, as inequality between ethnic groups increases, the prospects of interethnic marriages decline. Status equalization between ethnic groups promotes cross-ethnic ties. Insofar as intermarriage indicates social cohesion, reducing ethnic inequality in multiethnic societies may facilitate ethnic integration. Second, the effect of ethnic inequality is not uniform across ethnic groups. Endogamy remains high among certain groups even when socio-economic disparities diminish. I suggest this is because the ethnic norms and sanctions proscribing outmarriage are particularly powerful within these groups. Third, the social and political salience of ethnic boundaries may be distinct. Intermarriages can increase even as civil war violence intensifies. Ethnic divisions risk being overstated by assuming political attitudes also drive choices in the social sphere. I establish these findings in the deeply-divided society of Mindanao in the southern Philippines by analysing over 6.2 million marriages and comparing individual-level census data for the years 2000 and 2010. Mindanao is home to a longstanding insurgency, waged by rebels drawn from the native Muslim Moro population resentful of their minoritization and dispossession by Christian settlers.