The European Federal Union, commonly called the European Union or simply The EU, is a nation compromised of 29 federal states and 3 overseas territories. The bulk of the country on Earth is located within mainland Europe, with overseas holdings located in South America and the Atlantic Ocean. The European Union has two extraplanetary holdings: The Republic of Copernicus on Luna, and the recently-established Argyre Republic on Mars. With a population of 639 million, the EFU is the third most populous nation on Earth, approximately 2.71 billion behind the AEDU and 30 million ahead of the United States. The capital of the EU is Brussels, which functions as its own federal state, while the largest city is London, part of the Rotterham-Rome Axis.
With support from the United States, and facing the threat of the USSR on its eastern flank, the nations of Western Europe met in Strasbourg, France to discuss terms for closer political, military, and economic cooperation in order to help the continent recover and reorganize in the aftermath of World War II. This was also spurred by the collapse of European colonial empires after the African Wars of Independence, which led to a substantial "Europe First" movement that sought to abandon most foreign affairs and instead concentrate on domestic and local matters, now that most European nations no longer had significant overseas investments.
European Community & European Union
The subsequent Strasbourg Treaty of 1951 brought into existence the European Community, a coalition of 5 nations that announced their intentions to pursue closer partnerships with each other and begin negotiations in foreign affairs and economic matters as a unified bloc. Not only was this meant to act as a political statement to the Warsaw Pact, and as an act of recovery for a badly damaged continent, but it was also made with the purpose of preventing a war like World War II from ever happening again; by integrating the political systems, economies, and societies of European nations, any two nations going to war would suffer greatly from the disruption alone, discouraging wars between members.
The newly-founded European Community expanded gradually into a titan of politics. Less than a year after it's formation, the United Kingdom joined the EC, strengthening it's position and power within Europe. The first test of the Community's political power came in the 1970s with the Second Spanish Civil War, where the European Community assisted forces loyal to the Kingdom of Spain after it was revealed that the Soviet Union had been assisting communist forces in Andalucía and Valencia. By the end of the Civil War in 1978, the European Community had cemented itself as the main political entity in Europe. By the 1990s, it had expanded to include Germany, Denmark, Ireland, Austria, Spain, Portugal, and Greece, with other countries expressing interest in possibly joining after the end of the First Cold War.
As the First Cold War came to an end and the Warsaw Pact dissolved, the European Community stood as the only remaining political organization on the continent.