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 e.g. for digging by hand, the norm was of stone per day per brigade. These teams were pitted to compete against each other in surpassing the norms, and promises were made of shortened sentences, food and cash bonuses for those who would. After the construction, 12,000 prisoners were freed as a reward for their efforts. Meanwhile, about 12,000 workers died during the building process, according to the official records, while Anne Applebaum's estimate is 25,000 deaths. A carefully prepared visit in August 1933 to the White Sea–Baltic Canal may have hidden the worst of the brutality from a group of