Original: Until 2007, administratively, the whole island of Saint-Barthélemy was a French commune (commune de Saint-Barthélemy) part of Guadeloupe, which is an overseas région and overseas département of France, and therefore part of the European Union.
Simplified: Administratively, the whole island of Saint-Barthélemy was a French copmmune (commune de Saint-Barthélemy). It was part of Guadeloupe, which is an overseas région and overseas département of France.