Shortly after the start of the Pacific War, the island of New Guinea was invaded by the Japanese. Papua was the least affected region. Most of West Papua, at that time known as Dutch New Guinea, was occupied, as were large parts of the Territory of New Guinea (the former German New Guinea, which was also under Australian rule after World War I), but Papua was protected to a large extent by its southern location and the near-impassable Owen Stanley Ranges to the north. Civil administration was suspended during the war and both territories (Papua and New Guinea) were placed under martial law for the duration.