Central to many political and constitutional disputes in the Pacific Islands is the fact that cultural and national identities, and categories such as indigenous, are ambiguous and contested. This chapter addresses the transformation of cultural systems and ideologies from the colonial era through decolonisation, by focusing on political ideas, cultural and local identities, and changing forms of group action. It also addresses the implications of decolonisation and economic transformation for women. Scholars suggest various causes for increasing political and other violence, such as foreign education, the frustration of young people, power disparities between ethnic groups, conflicts between region and nation over resources, and a growing gap between rich and poor. During the colonial period, Melanesian tradition became conspicuous and contentious in two arenas, one of them being that debate about local beliefs and practices escalated in association with cargo cults, that well-known form of Melanesian millenarianism. In gender relations, a dynamic conjunction linked indigenous precedents and foreign ideas and institutions.