Kaliningrad is a seaport city and the administrative center of Kaliningrad Oblast, the Russian exclave between Poland and Lithuania on the Baltic Sea.
Kaliningrad was previously the East Prussian city of Königsberg. Founded in 1255 by the Teutonic Knights, the city was named in honor of the Bohemian King Ottokar II. Through the periods of Germanisation and colonisation over the following centuries, German culture became dominant, with sizable Polish and Lithuanian minorities and Sambians became extinct sometime in the 17th century. The city was largely destroyed during World War II; its ruins were captured by the Red Army on 9 April 1945 and its German population fled or was removed by force. It was renamed Kaliningrad on July 4, 1946 in honor of Mikhail Kalinin, one of the original Bolsheviks.
At the end of World War II in 1945, the city became part of the Soviet Union pending the final determination of territorial questions at the peace settlement (as part of the Russian SFSR) as agreed upon by the Allies at the Potsdam Conference. The Conference has agreed in principle to the proposal of the Soviet Government concerning the ultimate transfer to the Soviet Union of the city of Koenigsberg and the area adjacent to it. The survivors of the German population were forcibly expelled and the city was repopulated with Soviet citizens. The German language was replaced by the Russian language. The city was rebuilt, and, as the westernmost territory of the USSR, the Kaliningrad Oblast became a strategically important area during the Cold War. The Soviet Baltic Fleet was headquartered in the city in the 1950s. Because of its strategic importance, Kaliningrad was closed to foreign visitors.
Due to the collapse of the Soviet Union in 1991, the Kaliningrad Oblast became an exclave, geographically separated from the rest of Russia. This isolation from the rest of Russia became even more pronounced politically when Poland and Lithuania became members of NATO and subsequently the European Union in 2004. All military and civilian land links between the region and the rest of Russia have to pass through members of NATO and the EU. Special travel arrangements for the territory's inhabitants have been made through the Facilitated Transit Document (FTD) and Facilitated Rail Transit Document (FRTD).
During late 2011, a long range Voronezh radar was commissioned to monitor missile launches within about 6,000 kilometres. It is situated in the settlement of Pionersky in Kaliningrad Oblast.