Based on a comparative approach between different sites, this text deals with the circulation and territories of reggae. The elements of comparison emerge from the questions raised by these different sites. We go through an international exhibition on the musical diasporas of two former imperial capitals, "Paris and London. 1962-1989. Music Migrations", which raises the question of the relationship between music and anti-racist mobilizations in a context of postcolonial immigration. We continue by going to the symposiums / musical sessions "sound system outernational", where academics, musicians and actors of this music and sound practices participate, which raise the question of the sound dimension associated with this circulation of reggae in a transnational space but rooted in Caribbean and English worlds. We finish on the Marseilles reggae scene which presents a case of appropriation according to local issues, articulated to these media and migratory components.