The war that opposed France and Prussia in 1870 marked the entry of Europe into a new phase of confrontation that culminated with the Second World War.
Until then, the German nation had been the sleeping giant of Europe. While its territory and population were both larger than any of its neighbours in Central and Western Europe, Germany was a patchwork of small kingdoms and principalities that kept each other in check and were only very loosely confederated in a military alliance. The situation changed after the Napoleonic Wars, when the thousand year old Holy Roman Empire was disbanded and two powers, Austria and Prussia, had become the two dominant powers in Germany. The rivalry escalated into a full blown conflict that left Prussia as the sole super power. Prussia proceeded to federate all German states except Austria under its leadership and launched a rapid war of expansion against France, annexing Alsace and Eastern Lorraine, two regions of Germanic culture that had been part of France for a long time.
France's unexpected and humiliating defeat built a terrific level of resentment that led to two new wars between the two countries. Alsace and Lorraine changed sovereignty twice more until the they were finally returned to France in 1944.
The Franco-Prussian War
