Northern Dimension to include Estonia, Latvia, Lithuania, and Poland, the importance of the Northern Dimension has increased considerably: eight EU Member States (Denmark, Germany, Poland, Lithuania, Latvia, Estonia, Finland, and Sweden) surround the Baltic Sea, and the EU’s shared border with Russia has lengthened. Recent years have seen far-reaching changes in the geopolitical map of northern Europe. The Baltic States regained their independence in 1991. Finland and Sweden joined the EU in 1995, and Estonia, Latvia, Lithuania, and Poland in 2004. These events greatly increased the Northern and Baltic “presence” of the EU, and substantially lengthened the common border shared by the
Germany–Poland border the Slavic tribes. Over several centuries, it has moved eastwards, stabilized in the 14th century, and disappeared in the late 18th century with the partitions of Poland, in which Poland's neighbors, including the Kingdom of Prussia, annexed all of its territory. In 1871 Prussia became part of the German Empire. After Poland regained independence following World War I and the 123 years of partitions, a long German-Polish border was settled on, long (including a border with East Prussia). The border was partially shaped by the Treaty of Versailles and partially by plebiscites (East Prussian plebiscite and the Silesian plebiscite, the