German industry was heavily dependent on the import of iron ore from the northern Swedish mining district, and much of this ore was shipped through the northern Norwegian port of Narvik during the winter months.
Industri Jerman sangat bergantung pada impor bijih besi dari distrik penambangan Swedia utara, dan banyak dari bijih ini dikirim melalui pelabuhan Narvik di Norwegia bagian utara selama musim dingin.