In the wake of World War I and the Treaty of Versailles, the Schleswig region of Denmark and Germany faced significant changes in governance and national identity. The Treaty stipulated that plebiscites would be held to determine whether certain areas, including Schleswig, would belong to Denmark or Germany. On March 14, 1920, the second plebiscite took place in Zone II, an area wherein the population predominantly identified with German culture and language. The results revealed a clear preference among voters, with approximately 80% choosing to stay with Weimar Germany rather than join Denmark.

The plebiscite marked a significant moment in the region's history, reflecting the lingering divisions and historical grievances stemming from past conflicts, including the Second Schleswig War (1864). The success of the plebiscite in Zone II reinforced the boundaries established by World War I, ensuring that the region would not revert to Danish control. This outcome was noted for its reflection of local sentiments, as many residents feared that transitioning to Danish governance would disrupt their social fabric and economic stability.

The importance of the plebiscite extends beyond just the decision to remain part of Germany; it indicated the broader trends of nationalism and identity in post-war Europe. Such plebiscites were part of a larger movement, where the principle of self-determination was tested and contested, highlighting the complexities of national borders drawn in the post-war era. The League of Nations' involvement in overseeing the plebiscites was also significant, as it showcased early efforts at international governance, a process aimed at maintaining peace in a fracturing Europe.