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–Baltic Canal to 7). The Finns crossed the canal and captured Gabselga village east of it, but after a few days of fighting they were pushed back to the canal's western side. Soviet sappers blew up Lock No. 7 only on December 11, after the Red Army had already retreated from the area. Once the locks of the Povenets Ladder had been destroyed, water from the watershed lakes started to freely pour into Lake Onega through Povenets village, which was nearly completely destroyed by the flow. The route of the White Sea–Baltic Canal had become the front line, separating the Finnish troops