Why is unity so important to Europe?

Why is unity so important to Europe?

By Bryony Jones, CNN

November 4, 2011 -- Updated 1619 GMT (0019 HKT)

The leaders of Germany and France, Angela Merkel and Nicolas Sarkozy, are struggling to keep the European Union -- and the euro -- together in the face of the eurozone crisis.

While the idea of European unity goes back centuries, today's EU has its foundations in the post-WWII years, when politicians were determined to prevent such conflict from breaking out again.

French politician Robert Schuman is regarded as one of the founding fathers of the European Union -- he came up with the idea for its precursor, the European Coal and Steel Community.

The ECSC, which came into being with the signing of the Treaty of Paris, on 18 April 1951, was designed to make war between France and Germany "not merely unthinkable, but materially impossible."

The 1957 Treaty of Rome created the European Economic Community, under which the partner nations attempted to harmonize a raft of other policies, from agriculture and fisheries to monetary policy.

Over the decades, the EEC became the European Union, and expanded from the original six nations to today's 27 members, from Finland in the north to Malta in the south.

Seventeen of the 27 EU members are also part of the eurozone, sharing the single European currency, the euro, which was launched on 1 January 1999. Euro coins and banknotes were introduced three years later.

But the global economic crisis has caused major financial headaches for many member nations, sparking disunity and leading to fears Greece may become the first nation to pull out of the euro.