On September 12, in a development that advanced the long-anticipated end of Germany’s postwar division, officials from the German Democratic Republic (GDR, East Germany) and the Federal Republic of Germany (FRG, West Germany) announced the formal start of procedures intended to lead toward reunification. The declaration followed months of political upheaval in the East, mass public demonstrations, and rapid changes in the GDR’s leadership and policies earlier that year. Background Germany had been divided since 1949 into two states established in the aftermath of World War II and the emerging Cold War. The FRG developed as a liberal democratic state aligned with Western institutions, while the GDR was a socialist state within the Soviet sphere. For four decades the Inner German border and the Berlin Wall symbolized that division. Beginning in late 1989, popular protests across the GDR, along with reform pressures from within the ruling Socialist Unity Party (SED) and shifting Soviet policy under Mikhail Gorbachev, created political openings for change. Events Leading to the Announcement Throughout 1989 and into 1990, the GDR experienced growing civic mobilization: large demonstrations, the exodus of citizens through neighboring countries, and contested leadership transitions in East German institutions. These dynamics made clear that the status quo was unsustainable and pushed both German states toward negotiations over the future constitutional and political arrangements between them. Content and Immediate Implications The announcement on September 12 signaled agreement to begin formal intergovernmental procedures and legal steps aimed at unifying institutions and clarifying the constitutional route to reunification. While the specific legal instruments and timelines were matters for subsequent negotiation, the declaration publicly committed both governments to pursue political and administrative integration rather than indefinite separation. Immediate implications included initiating talks on law harmonization, citizenship, currency arrangements, and the status of East German institutions. International Context Any path to German reunification required engagement with the four wartime Allied powers (the United States, the Soviet Union, the United Kingdom, and France) and neighboring states, who had security and territorial concerns stemming from the postwar settlement. The European Community (later the European Union) and NATO were also central to diplomatic discussions. The September announcement therefore set in motion not only bilateral German negotiations but also concerted diplomacy with external powers to resolve questions of borders, alliances and military arrangements. Domestic Political Effects Within both German states, the formal start of reunification procedures intensified political debates. In the GDR, reformist and opposition groups sought guarantees that reunification would protect civil liberties and social welfare commitments. In the FRG, policymakers and parties discussed the economic, social and fiscal implications of integrating East Germany, including the condition of East German industry, property restitution, and social transfer costs. Legal and Administrative Challenges Practical obstacles loomed: aligning two distinct legal systems, integrating public administrations, and determining the status of GDR laws, institutions and public employees. Currency union, the recognition of property rights, pension harmonization and the handling of security services associated with the old regime were among the complex matters requiring negotiated solutions and phased implementation. Significance and Legacy The September 12 announcement marked a pivotal transition from mass protest and political collapse toward institutional and diplomatic processes aimed at reconstituting Germany as a single state. It represented a concrete step in a broader, historically consequential transformation in Europe: the end of Cold War-era divisions and the reshaping of European security and political structures. Subsequent months of negotiations, both bilateral and international, determined the precise legal route and timeline that would culminate in full political union. Notes on Sources and Certainty Contemporary reporting, governmental statements and later historical studies document the sequence of events in 1989–1990 that led to German reunification. Specific procedural details and the precise language of any September 12 declaration varied between East and West German sources and were elaborated in subsequent treaties and agreements. Where exact phrasing or a single unified text is not available, historians treat the date as the point at which formal procedural steps were publicly declared and pursued.