The effect of Italian colonialism on migration to Italy differed according to the pre-colonial social structure, a factor previously neglected by immigration theories. In Eritrea, precolonial Christianity, sharp class distinctions, and a strong state promoted interaction between colonizers and colonized. Eritrean nationalism emerged against Ethiopia; thus, no sharp break between Eritreans and Italians emerged. Two outgrowths of colonialism, the Eritrean national movement and religious ties, facilitate immigration and integration. In contrast, in Somalia, there was no strong state, few class differences, the dominant religion was Islam, and nationalists opposed Italian rule. Consequently, Somali developed few institutional ties to colonial authorities and few institutions provided resources to immigrants. Thus, Somali immigrants are few and are not well integrated into Italian society.