The Napoleonic Wars ended in 1815 with a peace settlement orchestrated by the brilliant Austrian foreign minister, Metternich. The peace settlement was known as "the Concert of Vienna" and kept the peace in Europe for the next 99 years with the exception of the Franco-Prussian War. The Concert of Vienna adjusted affairs in Europe so that each nation felt its national interests were protected, and, most importantly, maintained a delicate balance of power between European nations.



However, in 1815 Germany did not exist. There were dozens of "Germanic States", some very small, a few fairly large, where Germany is today. When Germany was created by uniting all these "Germanic States" into one single nation under the plans of the Prussian minister Bismarck, this was the appearance of a new, large nation in central Europe, which was not planned for nor accommodated under the Vienna peace plan of fifty years before. The very existence of a united Germany upset the delicate balance of power of the Concert of Vienna which had kept the peace for those fifty years. Alarmed at the appearance of a powerful new united neighbor on her border, France immediately picked a fight with the newly united Germany, started a war, and promptly lost it. This proved that not only was there a united Germany here to stay, but that Germany was a powerful nation capable of easily handling France, which had been considered one of the world's great powers. This made the arrangements of the Concert of Vienna out of date, and nations began making alliances with one another, to increase their feelings of security about what might happen if a large war came. It was these alliances which caused many European nations to be pulled into war in 1914, when the nations they were allied with went to war.