This monograph leans on former and contemporary ethnographical data. It clears and analyzes the principles and the fundamental values which base the order of the Wallisian society and its renewal. The thesis has four chapters: i) study of the land system where "households", appears as a central reference, an "ancestor-land"; ii) analysis of the kinship terms and of the kaiga/kutuga relationship systems (the distinction between man/woman and brother/sister relations is major here); iii) study of the components of the person starting from the study of the funeral rites. The different organization of these relational (and not substantial) components defines the various entities of the social world (humans, ancestors, deities, but also men and women, young and old people, superiors and inferiors); iv) presentation and analysis of the ceremonial gifts, themselves constituted of relations. Their circulation operate the renewal of life under the authority of the "king" and the island's chiefs. The conclusion proposes a synthesis on the ritual system, in connection with the order of the socio-cosmic world and the fate of the people whose life it organises.