the european union (abbreviation: eu) is a confederation of 27 member countries in europe established by the maastricht treaty in 1992-1993. the eu grew out of the european economic community (eec) which was established by the treaties of rome in 1957. it has created a common economic area with europe-wide laws allowing the citizens of eu countries to move and trade in other eu countries almost the same as they do on their own. nineteen of these countries also share the same type of money: the euro.