History of the North Sea the North Sea though they saw little action. The Austro-Prussian War (1866) resulted in Prussia's gaining full control of the Kiel Canal, allowing their Baltic ports access to the North Sea. France declared war on Prussia 19 July 1870 which initiated the Franco-Prussian War (1870–1871). The French Navy was, at the time far larger and superior to the North German Federal Navy, the Navy of the North German Confederation. Though the French did take a number of merchant ships bound to and from North Germany, shortages of manpower and coal, as well as conflicting orders, made the attempted blockade of
White Sea mostly targeting harp seal, ringed seal, herring, saffron cod, European smelt, Atlantic cod and Atlantic salmon. There is a developing seaweed industry. The White Sea is an important traffic centre of northwestern Russia, interconnecting various economic regions and providing an outlet to the foreign routes. The White Sea–Baltic Canal links it through Lake Onega to the Baltic Sea and the major city and port of Saint Petersburg. The Baltic Sea, in turn, is connected by the Volga–Baltic Waterway to the Volga River, Black, Caspian, and Azov seas. The major ports on the White Sea are Arkhangelsk, Belomorsk, Onega, Mezen, Kem,