There are two main religions in Japan: Shinto and Buddhism. Japanese people will probably claim to not be religious but still follow the Shinto rites and visit Buddhist temples.

Shinto

Shinto, which means "the way of the gods," does not have definitely defined gods. It involves a belief in the spirit within all things, whether they be alive or not. These spirits are called kami and are not technically gods, as Westerners would perceive it. There is kami for trees, rocks, the Emperor and the spirits of national heroes and famous scholars and officials.

There are a number of Shinto rituals. Some rituals are for wedding and birth ceremonies or for the launching of ships.

Shinto has been with the Japanese with ancient times. It has weathered tough times competing with the more elaborate and less vague Buddhism but is as much a part of Japan as sushi. Shinto also had struggles with the government. During the Meiji Restoration, Shinto almost became the national religion since it did so well as a rallying cry for the people of Japan. However, in 1884, the government declared it a cult and forbade the preaching of it. In 1945, Shinto was officially separated from state funding by the Allied forces occupation. However, Shinto emerged through all of this and 100,00 priests and 90,000 shrines strong today.

Buddhism

Buddhism was imported from China circa 550 AD. Buddhism was also a simple religion but was much more intellectual than Shinto. Buddhism was readily embraced by the aristocracy but took some time to become popular with the general population. Prince Shotoku (574-622) made it the State religion. Buddhism deals more with the afterlife and never replaced Shinto and never could. That's why the Japanese practice both.

Zen Buddhism

Zen Buddhism is the Japanese enhancement of regular Buddhism. Zen believers look within themselves to find Buddha. It has a philosophy of meditation and a belief that every human life is precious and important. The Japanese started a Buddhist movement known as Nichiren Shoshu. The movement was named after Nichiren (1222-1282) who was a monk that linked Buddhism to natural life and became very popular. He was also regarded with respect when he predicted the future, most notably the Mongols' attempted invasion of Japan.

Christianity

Less than 1% of Japan's population is Christian but they are a strong and persevering group. Christianity was brought by Francis Xavier in 1594. Christianity was at its strongest during the Shogun era and therefore was seen as a threat and many were persecuted. Hideyoshi even crucified 26 Christians. (Well, most of them were Christians but some Jesuits were killed by mistake as well.