One solution, which afterwards had the support of Napoleon III, would have been to partition Schleswig on the lines of nationality, assigning the Danish part to Denmark, the German to Holstein. This idea, which afterwards had supporters among both Danes and Germans, proved impracticable at the time owing to the intractable disposition of the majority on both sides. This solution was subsequently implemented by plebiscites in 1920 as a condition of the treaty of Versailles, and Northern Schleswig was returned to Denmark.