The history of Europe is long and complex, stretching back to the earliest civilizations and cultures that were present in the region. From the Roman Empire and the Middle Ages to the Renaissance and the Enlightenment, the continent has seen immense change through the ages. After the fall of the Roman Empire, Europe was divided by religion and language and made up of individual kingdoms, feudal domains and city-states. As the political situation became ever more complex, the Enlightenment period saw the rise of a new form of government – nationalism – and the emergence of the nation-state. As Europe industrialized and colonized beyond its own borders, two world wars in the 20th century would leave a major imprint on the continent. In the wake of these conflicts, the European Union was formed in 1993 in order to promote peace, democracy, and economic integration in the region.