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
1872 Baltic Sea flood 1872 Baltic Sea flood The 1872 Baltic Sea flood (), often referred to as a storm flood, ravaged the Baltic Sea coast from Denmark to Pomerania, also affecting Sweden, during the night between 12–13 November 1872 and was, until then, the worst storm surge in the Baltic. The highest recorded peak water level was about 3.3 m above sea level (NN). In the days before the storm tide, a storm blew from the southwest across the Baltic that drove the sea towards Finland and "Balticum". The result was flooding there and extreme low water levels on the Danish-German coastlines. As