In 1989, the Berlin Wall was opened, the Soviet Union collapsed, and EastGermany was reunited with West Germany in 1990. In 1998-1999, Germany was one of the founding countries of the eurozone. Germany remains one of the economic powerhouses of Europe, contributing about one-quarter of the eurozone’s annual gross domestic product. In the early 2010s, Germany played a critical role in trying to resolve the escalating euro crisis, especially concerning Greece and other Southern European nations.