Recently, the historical validity of concepts of aboriginality has been questioned. It is argued here that aboriginality has been and remains a significant feature of identity and a source of cultural renewal in a rapidly changing world. The nature of aboriginality must always be qualified and contextualized. In Canada, a specific notion of aboriginality is an administrative tool of government that at all times is partially accepted and partially opposed by those so defined and administrated. In the example described here, the missionary William Duncan denied the concept of aboriginality presented by his Tsimshian flock as well as that enunciated by the Canadian government. Today, the descendants of these mission communities have ontological identities linked not only to Christian modernity but also to Tsimshian aboriginality defined one way by the government and quite differently by each local community.