Szczecin (; Polish pronunciation; German and Swedish: Stettin, known also by other alternative names) is the capital and largest city of the West Pomeranian Voivodeship in Poland. Located near the Baltic Sea and the German border, it is a major seaport and Poland's seventh-largest city. As of June 2011, the population was 407,811. Szczecin is located on the Oder, south of the Szczecin Lagoon and the Bay of Pomerania. The city is situated along the southwestern shore of Dąbie Lake, on both sides of the Oder and on several large islands between the western and eastern branches of the river. Szczecin is adjacent to the town of Police and is the urban centre of the Szczecin agglomeration, an extended metropolitan area that includes communities in the German states of Brandenburg and Mecklenburg-Vorpommern. The city's recorded history began in the 8th century as a Slavic Pomeranian stronghold, built at the site of the Ducal castle. In the 12th century, when Szczecin had become one of Pomerania's main urban centres, it lost its independence to Piast Poland, the Duchy of Saxony, the Holy Roman Empire and Denmark. At the same time, the House of Griffins established themselves as local rulers, the population was Christianized, and German settlers arrived from Western European states. The native Slavic population was subjected to discrimination and Germanization in the following centuries. Between 1237 and 1243, the town was rebuilt, granted extensive autonomy rights and eventually joined the Hanseatic League. After the Treaty of Stettin in 1630, the town came under the control of the Swedish Empire. It was fortified and remained a Swedish-controlled fortress until 1720, when it was acquired by the Kingdom of Prussia and became the capital of the Province of Pomerania, which after 1870 was part of the German Empire. In the late-19th century Stettin became an industrial town, vastly increasing in size and population, and served as a major port for Berlin. During the Nazi era, opposition groups and minorities were persecuted and treated as enemies. By the end of World War II Stettin's status was in doubt, and the Soviet occupation authorities at first appointed officials from the city's almost entirely German pre-war population. In July 1945, however, Polish authorities were permitted to take power. Stettin was renamed Szczecin and became part of the newly established the Polish People's Republic, and from 1989 the Republic of Poland. After the flight and expulsion of Germans from Poland during and after World War II and Polish settlement in the newly acquired territories, Szczecin became the administrative and industrial centre of Polish Western Pomerania. It is now the site of the University of Szczecin, Pomeranian Medical University, Maritime University of Szczecin, West Pomeranian University of Technology, and Art Academy of Szczecin, and the see of the Roman Catholic Archdiocese of Szczecin-Kamień. From 1999 onwards, Szczecin has served as the site of the headquarters of NATO's Multinational Corps Northeast.