Man'yōshū in the context of Kamikaze (typhoon)

The small group of Hachijō dialects (八丈方言, Hachijō hōgen), natively called Shima Kotoba (島言葉; [ɕima kotoba], "island speech"), are, depending on classification, either the most divergent form of Japanese, or comprise a branch of Japonic languages (alongside mainland Japanese, Northern Ryukyuan, and Southern Ryukyuan). Hachijō is currently spoken on two of the Izu Islands south of Tokyo (Hachijō-jima and the smaller Aogashima) as well as on the Daitō Islands of Okinawa Prefecture, which were settled from Hachijō-jima in the Meiji period. It was also previously spoken on the island of Hachijō-kojima, which is now abandoned. Based on the criterion of mutual intelligibility, Hachijō may be considered a distinct Japonic language, rather than a dialect of Japanese.

Hachijō is a descendant of Eastern Old Japanese, retaining several unique grammatical and phonetic features recorded in the Azuma-dialect poems of the 8th-century Man'yōshū and the Fudoki of Hitachi Province. Hachijō also has lexical similarities with the dialects of Kyushu and even the Ryukyuan languages; it is not clear if these indicate that the southern Izu islands were settled from that region, if they are loans brought by sailors traveling among the southern islands, or if they might be independent retentions from Old Japanese.

Tsukuyomi-no-Mikoto (ツクヨミノミコト, 月読命), or simply Tsukuyomi (ツクヨミ, 月読) or Tsukiyomi (ツキヨミ), is the moon kami in Japanese mythology and the Shinto religion. The name "Tsukuyomi" is a compound of the Old Japanese words tsuku (月; "moon, month", becoming modern Japanese tsuki) and yomi (読み; "reading, counting"). The Nihon Shoki mentions this name spelled as Tsukuyumi (月弓; "moon bow"), but this yumi is likely a variation in pronunciation of yomi. An alternative interpretation is that his name is a combination of tsukiyo (月夜; "moonlit night") and mi (見; "looking, watching"). -no-Mikoto is a common honorific appended to the names of Kami; it may be understood as similar to the English honorific 'the Great'.

In Man'yōshū, Tsukuyomi's name is sometimes rendered as Tsukuyomi Otoko (月讀壮士; "moon-reading man"), implying that he is male.

Emperor Tenmu (also romanized Temmu, c. 630 – 686) was 40th Emperor of Japan according to the traditional order of succession. He was born Prince Ōama around 630, the son of Emperor Jomei and his consort Princess Takara. Ruling from 673 to 686, during the Asuka period, his life is mainly documented by the chronicles Nihon Shoki and Kojiki, as well as the poetry collection Man'yōshū.

Little is known of Ōama's early life. During the rule of his elder brother Tenji, Ōama was ambiguously favored as his successor, but was gradually bypassed in favor of Tenji's son Prince Ōtomo. Tenji allegedly offered Ōama the throne during an illness in 671, but fearing a conspiracy against him, Ōama declined and left to serve as a monk at Yoshino Palace. Tenji died soon after. The following year, Ōama received word that Ōtomo, now ruler, was planning to kill him. He fled Yoshino with a group of followers, beginning the Jinshin War. Along with a group of retainers and the governor of Ise Province, Ōama was able to block off the mountain passes to the northern and eastern provinces, where he raised an army against his nephew. Ōtomo was defeated and forced to commit suicide. Ōama took the throne under the name Tenmu.

Man'yōgana (万葉仮名; Japanese pronunciation: [maɰ̃joꜜːɡana] or [maɰ̃joːɡana]) is an ancient writing system that uses Chinese characters to represent the Japanese language. It was the first known kana system to be developed as a means to represent the Japanese language phonetically. The date of the earliest usage of this type of kana is not clear, but it was in use since at least the mid-7th century. The name "man'yōgana" derives from the Man'yōshū, a Japanese poetry anthology from the Nara period written with man'yōgana.

Texts using the system also often use Chinese characters for their meaning, but man'yōgana refers to such characters only when they are used to represent a phonetic value. The values were derived from the contemporary Chinese pronunciation, but native Japanese readings of the character were also sometimes used. For example, 木 (whose character means 'tree') could represent /mo/ (based on Middle Chinese [məwk]), /ko/, or /kwi/ (meaning 'tree' in Old Japanese).

Old Japanese (上代日本語, Jōdai Nihon-go) is the oldest attested stage of the Japanese language, recorded in documents from the Nara period (8th century). It became Early Middle Japanese in the succeeding Heian period.Old Japanese is an early member of the Japonic language family. No genetic links to other language families have been proven.

The bulk of the Old Japanese corpus consists of poetry, especially the Man'yōshū, with a smaller number of formal prose works. These texts were written using man'yōgana, a writing system that employs Chinese characters as syllabograms or (occasionally) logograms. The language featured a few phonological differences from later forms, such as a simpler syllable structure and distinctions between several pairs of syllables that have been pronounced identically since Early Middle Japanese. The phonetic realization of these distinctions is uncertain. Internal reconstruction points to a pre-Old Japanese phase with fewer consonants and vowels.