Japan's Indigenous religion of Shinto is largely rooted in animism, which believes there are thousands of “kami,” or spirits, inhabiting nature. It's closely linked to the country's imperial family: Around 1870, Japan made Shinto the state religion and used imperial worship to fan ultra-nationalism and support for World War II, which was fought in the name of the emperor. Japan's U.S.-drafted post-war constitution ensures freedom of religion and the separation of religion and state, though the conservative government today still places great importance on imperial worshipping.