The transition of French Guiana, Guadeloupe, Martinique, and Réunion into overseas départements of France marked a significant alteration in the administrative governance of these territories. This legal designation on March 19, 1946, was achieved following a notable shift in French policy, particularly influenced by the aftermath of World War II and growing calls for decolonization. The territories were now aligned more closely with mainland France, which came with expanded rights and benefits for the citizens inhabiting these regions.

Prior to this change, these territories had been treated as colonies, suffering from limited political representation and economic disparities when compared to their continental counterparts. By establishing these islands and territories as départements, France acknowledged their integral role within the French Republic. This new status allowed inhabitants to participate more directly in national governance and benefit from the same social and legal protections afforded to mainland citizens.

This shift contributed to a transformation in the identity of these territories, embracing a dual identity as part of France while also maintaining unique cultural elements. It also set a precedent for future administrative reforms in the context of France's global colonial legacy, affecting their political landscape significantly. Overall, this decision demonstrated a reorientation in France towards incorporating its distant territories into the national fold, fostering a sense of collective citizenship.