Great Britain has always been ambivalent about being tied to Europe. The U.K. joined the European Economic Community in 1973, and two years later, it held a referendum on whether it should leave. Here, members of the Labour Party hold a 1975 news conference to explain why they favor pulling out of the European body. However, U.K. citizens voted 2 to 1 to remain in the EEC at that time. (Getty Images)