After the end of the Second World War, Japan came under international control. Japan became an important friend of the US when it entered into the Cold war with Korea. Over next few years, many political, economic and social changes took place. The Japanese Diet came into being. In 1951, USA and 45 other countries signed an agreement with Japan, and Japan again became an independent nation with full power (a country with full sovereignty) on 28th April 1952.