Copenhagen is the capital city of Denmark. It was founded around 1000 by Sweyn I Forkbeard and his son Canute the Great. It was only a fishing village by the name of "Havn" (harbour) until the middle of the 12th century when it grew in importance after coming into the possession of the Bishop Absalon, who fortified it in 1167. The excellent harbour encouraged Copenhagen's growth until it became an important centre of commerce. During World War II Copenhagen was occupied by German troops along with the rest of the country from 9th of April 1940 until 4th of May 1945. In August 1943, when the government's collaboration with the occupation forces collapsed, several ships where sunk in Copenhagen Harbour by the Royal Danish Navy to prevent them being used by the Germans. The city has grown greatly since the war, in the seventies using the so-called five-finger-plan of communter trainlines to surrounding towns and suburbs.