Expatriates - second-rate citizens, somtimes seen as traitors to the homeland - often deprived of all or part of their political rights, were in the 19th and 20th centuries the poor children of the nation. For three decades, in light of evolutions of the global migratory system and technological transformations allowing long-distance relations, these migrants retain closer ties to their respective countries of origin.

They actively participate in debates about the definition or redefinition of "nation" and favor the creation of a trans-national negotiation space for the satisfaction of their claims to nationality, political representation, etc.

While out of sight, they live forever closer to the minds of their homelands. Several nations both emerging and developed implement political ties via nationals living abroad. The focus of this innovative work is precisely to present, based on research of approximately fifty countries, a panorama of these transformations, both historical and contemporary.

Stéphane Dufoix is an Associate Professor of Sociology at l'Université Paris-Ouest Nanterre la Défense and a member of the Institut universitaire de France. Carine Guerassimoff, Sinologist and Political Scientist, is an Associate Researcher at the SEDET-Université Paris VII Laboratory. Anne de Tinguy is a Professor at the Universités l'INALCO and at CERI- Sciences Po.