The euro came into existence on 1 January 1999, although it had been a goal of the European Union (EU) and its predecessors since the 1960s. After tough negotiations, particularly due to opposition from the United Kingdom, the Maastricht Treaty entered into force in 1993 with the goal of creating an economic and monetary union by 1999 for all EU states except the UK and Denmark (even though Denmark has a fixed exchange rate policy with the euro).

In 1999 the currency was born virtually and in 2002 notes and coins began to circulate. It rapidly took over from the former national currencies and slowly expanded behind the rest of the EU. In 2009 the Lisbon Treaty finalised its political authority, the Eurogroup, alongside the European Central Bank.

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