Believed to be an indigenous religion of Japan, Shintoism (or Shinto) involved the worshipping of kami and prescribed shrine rituals as a way of showing respect and devotion. The term was not in use until the 19th century.

Shinto is the religious structure that provides definition and a framework in which the practitioner can navigate the worship of specific kami. Shintoism is also believed to encompass the indigenous animistic beliefs of the Japanese and was an attempt to formalize different types of beliefs into a cohesive structure.

The word kami is the collective term used to describe the representation of what can be referred to as beings (or deities) found within such things as mountains and rivers. Deceased persons are sometimes able to become kami; however, this is a rare occurrence.

The written characters that make the word Shinto consist of two kanji, the first being shin (meaning "god" but also translated as "kami") and the second being tao (meaning "path"). The literal translation means "way of the gods". It is believed that the Yamato imperial court systematically deployed kami worship as a religious system during the third century c.e.

Shinto is widely recognized as an essentially Japanese religious system, having come into existence during the animistic Jomon Period (12,000 to 400 b.c.e.) and practiced by rural rice-cultivating peoples from the Yayoi Period (400 b.c.e. to 300 c.e.).

Before the Meiji Restoration in 1868, which saw Shinto becoming the sanctioned religion, there were three distinct forms of Shinto, or more appropriately, kami worship: These were Rural, Shrine, and Imperial Shinto. Before the intervention of the imperial state kami worship was, at best, disorganized and highly individualistic. From the fifth century c.e. Shinto practices amalgamated with Mahayana Buddhist and Confucian theology.

Shinto’s amalgamation with Buddhism and the ritualistic nature of Buddhist practices contributed to its remarkable integration into all levels of society, from the imperial family to the rural population. It is believed that the naming of the religion occurred as a way of distinguishing it from Buddhism and Confucianism.

Rural kami worship was often referred to as folk Shinto. In order to ensure prosperous crops and a harmonious village life kami would be worshipped through rituals designed to appeal to or appease the deities.

Each region in Japan was thought to have different rituals concerning the kami in their area, and each ritual was defined by the type of kami worshipped (such as rice cultivation and fish farming), hence different regions in Japan would have had entirely different and diverse systems of worship.

As agricultural developments increased and society underwent social and political change, ritual was increasingly employed to ensure a balance between the deities (kami) and the people. As society modernized so did the need for a codified structure of religion and religious practices.

Shrine Shinto and imperial Shinto are similar in that they were dependent upon kami worship as ritual. During the beginnings of the imperial state an official network of shrines was established, and through imperial decrees and ritualized (and state-controlled) prayers (norito) the kami system was formalized.

Chinese influences and concepts of deities during the Yamato court, such as ama-tsu-kami (heavenly deities), also contributed to the continual construction of Shintoism. The majority of information obtained from primary sources concerning Shinto comes from those written during the Yamato court era.

The construction of ritsuryo law (Japanese imperial law) focused particularly on shrine rituals that meant that many indigenous rituals or practices had not been written down. Imperial Shinto practices are more likely to have survived in historical record, as imperial households commissioned such records.

One such practice is the continual use of clerical titles denoting Shinto priests and practitioners in relation to their duties at various shrines. The highest-ranking priest or priestess in Japan is referred to as Saishu and is affiliated with the Grand Shrine of Ise.

A member of the imperial family most often holds this position. The lowest-ranking Shinto priest is the Toya, a part-time layperson chosen from village members to enter the shine for a specific amount of time.

Women were originally allowed to hold ceremonial positions within Shinto; however, as the religion underwent a metamorphosis from a rural-based practice to an imperial one they were increasingly relegated to positions that entailed less power, as assistants to the male members of the priesthood.

The oldest known texts in which Shinto practices appear is the 712 c.e. Kojiki (Record of ancient matters) and the 720 c.e. Nihongi (Chronicles of Japan). Both texts make mention of the belief that two kami (Izanami and Izanagi) created Japan.

Izanami gives birth to a kami of fire but dies in the process and resides in a place called Yomi no Kuni (Land of Darkness). Izanagi is shocked to witness Izanami in such a place and returns to the living, stopping on the way to wash himself of his visit to Yomi no Kuni.

The stories indicate an early belief in death as a pollution of the living and are thought to have guided the creation and formulation of other Shinto practices. The chronicles also legitimized the rule of Emperor Mimakiiri-hiko by ascribing him the name hatsu-kuni-shirasu sumera-mikoto (First Emperor to Rule the Realm).

The emperor initiated a state-sponsored adoption of kami worship that included all members of the royal family and the elite ruling members of society. Before this, kami worship lay in the hands of the local rulers and was based more upon shamanistic principles then ritualized worship.

Kami were, and still are, found in prominent and often strategic locations throughout Japan. The original underlying foundation of Shinto is the worship of kami to ensure prosperity, health, and an abundance of food and supplies.

The Yamato court focused on the Mount Miwa kami called Omononushi, which appeared in the form of a snake and was the subject of agricultural ritual. The area was fertile and consistently provided sustenance for the population, thus the kami was considered powerful.

Strategic sites such as the opening of a sea route also had important kami associated with them, such as Sumiyoshi, the kami of Naniwazu (Osaka). However, while kami tied to the environment were viewed as important, the Yamato court also worshipped kami spirits found in ritual objects and objects such as ceremonial weapons.

This type of worship became centralized in court life as it pointed toward the power of the court and enabled the transference of power through an object (for example, kami spirits embodied within a ceremonial sword) that was readily visible.

Shinto became a structured religious system by the systematic integration of kami worship into early imperial Japanese law and society. It is an indigenous religion that has also absorbed Buddhist and some Confucian rituals and philosophies.

Shintoism is notoriously difficult to define, especially in light of the fact that the rituals associated with the religion were often fluid in their approach and highly interchangeable depending on the circumstances of offering.