<human>:  What is the history of the European Union?
<bot>: The European Union (EU) was initially established after World War II as the European Coal and Steel Community in 1951 by six European countries—Belgium, France, Germany, Italy, Luxembourg, and the Netherlands. This union was created to promote economic and political cooperation among its members. The European Economic Community (EEC), commonly referred to as the "Common Market," was established in 1957, and by the early 1970s, the majority of Western European nations had joined the EEC. The purpose of the EEC was to promote free trade, the free movement of people, and the adoption of common standards in areas such as taxes and employment. In 1993, the Maastricht Treaty further extended the powers of the EU, introducing new areas of cooperation such as a single currency, the euro, and a common foreign and security policy. In 2016, the Treaty of Lisbon entered into force, making the EU an international legal personality and widening its powers to include areas such as energy, the environment, and justice and home affairs. Today, the European Union consists of 27 member states and has become a major economic and political actor on the international stage.