Japan slowly became a democracy following the end of World War II in 1945. It took 6 years of occupation and a new constitution written in 1946 to bring about the change.
As part of the new constitution, the power was removed from the Emperor and his family line and passed to the people of Japan. Along with this change, the country renounced war and gave up its right to have a military force. The life of the people changed all around the country. Tenant farmers were given ownership of the land the worked and industrial workers were allowed to form unions to protect their rights and wages.