A large contributor to the Franco-Prussian war on the individual level was the the deceitful diplomacy implemented by Otto Von Bismarck concerning the succession of the Austrian throne. The balance of power in Europe had been disturbed by Prussia's victory over Austria in the Seven Weeks War of 1866. This, along with the insulting Ems Dispatch, provided incentive for a French attack on Prussia. German Unification was the ultimate goal of Prussia, who inspired nationalism to achieve said goal. However, nationalism was prevalent in France as well. .
The Congress of Vienna, finalized in 1815, attempted to establish a balance of powers in Europe that would prevent future wars. Through a redistribution of territories, the treaty was rather successful in that regard until the Austro-Prussian War of 1866. Prussia defeated Austria in this "Seven Weeks War." As a result, the latter was no longer a part of the German Confederation and "left Prussia dominant in German politics" (Wiki). This redistribution of territories upset the balance of power. The North German Confederation replaced the German Confederation. Eventually, southern German states were included as nationalism rose through fighting the Franco-Prussian War.
The Ems Dispatch, a telegram describing the course of an encounter between French Ambassador, Vincent Benedetti, and Prussian King, Wilhelm I, was a powerful catalyst of the war. The two diplomats met unofficially to discuss the succession of the Spanish throne. Prussian Prince Leopold was a candidate. This was unacceptable to the French, who feared encirclement of Prussian influence. Shortly after the Ems Dispatch was released to the public, France declared war on Prussia. The version of the Ems Dispatch that was released only covered the gist of the discussions that took place. The two main points were that France demanded that Wilhelm would never again allow a Prussian candidacy for the Spanish throne "under threat of war; and Wilhelm had refused" (Taylor 121).