réunification

Réunification, or reunification, is the process by which previously divided political entities are restored into a single sovereign state. It typically follows periods of separation caused by war, occupation, ideological division, or political upheaval. Reunification often requires legal and constitutional changes, negotiated treaties, and, in many cases, referendums to align institutions, citizenship, borders, and economic systems. While it seeks to recover historic unity, it can raise questions of legitimacy, especially for communities with divergent national identities or memories of the division.

Examples include the German reunification of 1990, when the German Democratic Republic joined the Federal Republic of Germany through a series of policy steps and the reunification treaty, followed by rapid economic and administrative integration. Other cases include the unification of North and South Yemen in 1990, achieved by political agreement after decades of separate administrations, and Vietnam’s reunification in 1976 after the end of the Vietnam War. The Korean Peninsula remains diplomatically divided rather than reunified, illustrating that the outcome may differ widely in practice.

Scholars distinguish reunification from annexation or incorporation by emphasizing consent, international law, and democratic processes. Successful reunification tends to require reconciliation measures, transitional justice if needed, and strategies to address economic disparities and social integration, to sustain long-term political legitimacy.