Although there are several significant differences, the formation of the United States has a great deal in common with the forming of the European Union. Below, some similarities and differences are analyzed.

Similarities
By the time the American Revolution had come, the various states under British rule had already established their own identities, just as European nations have for centuries. As a result, each state was reluctant to surrender its identity to be part of a larger whole. The first state constitutions established after the Revolutionary War, which demonstrate a general distrust of governmental power, reflects this fear. Even during the Revolution, there was no real national government because the people saw centralized government as tyrannical thanks to the British. Similarly, nations such as Britain are reluctant to surrender power to the European Union. After several forceful attempts to unite Europe (Charlemagne, Napoleon I, Hitler), nationalism in European countries strengthened and made them reluctant to lose sovereignty. As is discussed in the section on nationalism and the EU, it is each nation's long history and sense of identity that makes such a union difficult.

However, there is an underlying similarity above all others that work for both unions, the fight for survival. Prior to becoming an independent country, the people of the United States felt oppressed by the various restrictions under Britain which they felt had led to arbitrary rule. It was felt that, in order to survive and preserve an acceptable way of life in accordance with Enlightenment view of the time, British rule had to be eliminated in a fight that the states could only survive together. After World War II, Europe finally realized that if they were to remain dominant in world affairs, they would have to posses political unity and command resources comparable to that of the United States. The North Atlantic Treaty Organization and rise of the Soviet Union also helped the cause by offering a common enemy.

Both the US and the EU have dealt with differences between member states. Like the US's Articles of Confederation, which required 9 out of 13 (60%) votes to take action, the EU's Council of Ministers requires that at least 62 percent of the Union's population agrees to an action before it is taken.

During the Revolutionary War, it was realized that a strong central government would be needed to ensure the US's independence. However, the committee that drew up the plans for such a government was rejected outright by the states because it compromised the sovereignty of the state. Although there wasn't as much of a widespread reaction in Europe, the implementation of the euro dollar brought resistance mainly from Britain and the Netherlands. The US's Constitutional Convention, which took place primarily due to an unacceptably weak government and economic problems (lower inflation) during the late 1700s, the EU's common market further supports the idea of unification by having each member country adopt a single currency to lower inflation. In both cases, member states and nations were gradually introduced into a greater political union through economic necessity.

Differences
Although both the US and EU have many different constituents, the EU is without question a far more difficult undertaking. The nations in the EU have existed since the founding of western civilization, which is obviously longer than the existence of states in the US. As a result of this long history, nations in the EU have developed a very distinct national identities. Britain and its glorious isolation is especially resistant to the EU because of this fear. Additionally, the two World Wars that have been fought in Europe have no doubt produced some distrust within the union, which is in part also responsible for the formation of it. However, these politics did not play a significant role in the formation of the US. Rather, the integration of states into the union was far easier because there were not such legacies.

Another difference between the US and EU is the way in which the government is structured. The US has two legislative bodies, the Senate and House of Representatives. In the House, members are elected based on population of the state they come from. In the Senate, however, there are two representatives from each state regardless. On the other hand, the Council of the European Union, which is the EU's lawmaking body and makes the majority of important decisions, gives each country's representative a certain amount of votes based on population. In other words, the country with the greatest number of people has the edge.

During the post-Revolution time in America, a depression took hold and there were few interests other than learning to live with independence. However, the EU member nations have far more differing interests and as a result are more reluctant to surrendering power to a new supranational organization. Also, there is a language barrier that the EU has to contend with which the US never did. This is important because language is one of the identifying marks of a nation and culture. It will take more than a constitution to unite Europe's many different peoples.

But overall, the histories of both the US and the EU are very similar. Both began unions that worked gradually from economic to political unification. Although the history of Europe is somewhat different from the United States, there were definitely common developmental issues faced by both supra state/supranational organizations.