The background of the war goes back to the First European War where Prussia and Austria were thoroughly humiliated, and the creation of the Confederation of the Rhine brought into play a new and powerful enemy for both of them. As Prussia and Austria built up a new military in the decades that followed the First European War, the Confederation of the Rhine became more and more centralized in the terms of military. The Confederated Rhineland Army had been established in 1838 to create a single army for Confederation, and had been supported and built by the French Empire. The clear military build-ups in Germany began to increase political tensions between the neighboring powers.