Colonization and decolonization are theorized at the intersection of Critical Junctures Theory and Power Basis Theory. This framework allows human agency to be conceptualized at micro-, meso-, and macro-levels, where individuals act on behalf of collectives. Their actions decide whether critical junctures in history (moments of potential for substantive change) result in continuity (no change), anchoring (continuity amid change with new elements), or rupture. We apply this framework to European colonization of the world, which is the temporal scene for contemporary social justice. Several critical junctures in New Zealand history are analyzed as part of its historical trajectory and narrated through changes in its symbology (system of meaning) and technology of state, as well as the identity space it encompasses (indigenous Māori and British colonizers). The impact of this historical trajectory on the social structure of New Zealand, including its national identity and government, is considered and connected to the overarching theoretical framework.