ON MARCH 25th 1957, with the shadow of the second world war still hanging over them, six European countries signed the founding treaty of a new sort of international club. The European Union, as the club came to be called, achieved success on a scale its founders could barely have imagined, not only underpinning peace on the continent but creating a single market as well as a single currency, and bringing into its fold ex-dictatorships to the south and ex-communist countries to the east, as it expanded from six members to 28. Yet even as today’s European leaders gather in Rome this weekend to celebrate the 60th anniversary, they know their project is in big trouble.
source: Can Europe be saved?
I read this paragraph in this week's The Economist. Could somebody explains the bold part for me? I don't get it since I don't quite know European history. And in this case, as I understand, "bring into" seems to mean "take into", am I right?