Early Shinto (See Shinto) envisioned a standard northern Asian cosmology made up of an upper world or Heaven (Takamanohara) for the gods, a middle world (Nakatsukuni) for humans, and an underworld (Yomi) for the dead. Yet simultaneously, Shinto understood the universe as the world with an adjacent eternal paradise (Tokoyo) across the sea. Under the influence of Chinese culture there was a drive to compile and standardize Shinto myths that had formerly belonged to regional and family groups. This drive for standardization coincided with the political drive for national unification and began to take concrete form during the reign of the Emperor Temmu (672–687). The culmination of the movement for mythological unity came with the creation of the two primary sacred books of Shinto, the Kojiki (See Kojiki) and the Nihongi (See Nihongi), early in the eighth century. It is in these books and other early eighth-century texts (for example, the Fudoki and the Sendai kujihongi) that the purest form of Shinto mythology is found. They contain the stories and descriptions of the Shinto deities or spirits called kamis (See Kamis), as opposed to the amalgamation of Buddhist (See Japanese Buddhism, Japanese Buddhas) and Shinto deities that became popular with the advent of Buddhism in Japan. Perhaps the most important of the anthropomorphic Shinto deities is the sun goddess Amaterasu (See Amaterasu), the patroness and ancestor of the Japanese emperors. It was her relatives and descendants who founded the Japanese nation. In the beginning, when Earth and Heaven separated, kamis appeared, including Izanagi and his wife Izanami (See Izanagi and Izanami), who created the natural world and various clans before their tragic separation and enmity. Their most important offspring were Amaterasu, the moon god Tsukiyomi no Mikoto, and the underworld god Susanowo (See Susanowo). It was Susanowo's offspring Okuninushi no Kami (See Okuninushi) who ruled Japan until the coming of Ninigi no Mikoto (See Ninigi), the grandson of Amaterasu (See Izumo Cycle). But it was Ninigi's grandson Jimmu Tenno (See Jimmu Tenno) who reigned as the first emperor.
