ter the Second World War, the town's population broke the 100,000 mark for a short time, thereby making Flensburg a city (Gro�stadt) under one traditional definition. The population later sank below that mark, however.
In the years after the Second World War, there was in South Schleswig, and particularly in Flensburg a strong pro-Danish movement connected with the idea of the "Eider Politics". Their goal was for the town, and indeed all or most of Schleswig � the whole area north of the river Eider�-to be united with Denmark. In the years following 1945, Flensburg's town council was dominated by Danish parties, and the town had a Danish mayor.
The town of Flensburg profited from the planned location of military installations. Since German Reunification, the number of soldiers has dropped to about 8,000. Since Denmark's entry into the European Economic Community (now the European Union), border trade has played an important role in Flensburg's economic life. Some Danish businesses, such as Danfoss, have set up shop just south of the border for tax reasons.
In 1970, the Flensburg district was expanded to include the municipalities in the Amt of Medelby, formerly in the S�dtondern district, and in 1974 it was united with the Schleswig district to form the district of Schleswig-Flensburg, whose district seat was the town of Schleswig. Flensburg thereby lost its function as a district seat, but it remained an independent (district-free) town.
Population figures are for respective municipal areas through time. Until 1870, figures are mostly estimates, and thereafter census results or official projections from either statistical offices or the town administration itself
