World War I and World War II had a profound impact on nation states in Europe. The two wars resulted in the redrawing of borders, the displacement of millions of people, and the destruction of many cities and towns. The two wars also led to the rise of totalitarian regimes in some countries, such as Nazi Germany, and the weakening of monarchies in others, such as the Austro-Hungarian Empire. Additionally, the two wars led to the emergence of the United Nations and the establishment of the European Union.