Kamakura, Kanagawa in the context of "Tennō"

The emperor of Japan is the hereditary monarch and head of state of Japan. The emperor is defined by the Constitution of Japan as the symbol of the Japanese state and the unity of the Japanese people, his position deriving from "the will of the people with whom resides sovereign power". The Imperial Household Law governs the line of imperial succession. Pursuant to his constitutional role as a national symbol, and in accordance with rulings by the Supreme Court of Japan, the emperor is personally immune from prosecution. By virtue of his position as the head of the Imperial House, the emperor is also recognized as the head of the Shinto religion, which holds him to be the direct descendant of the sun goddess Amaterasu. According to tradition, the office of emperor was created in the 7th century BC, but the first historically verifiable emperors appear around the 5th or 6th centuries AD.

The role of the emperor of Japan has historically alternated between a largely ceremonial symbolic role and that of an actual imperial ruler. Since the establishment of the first shogunate in 1192, the emperors of Japan have rarely taken on a role as supreme battlefield commander, unlike many Western monarchs. Japanese emperors have nearly always been controlled by external political forces, to varying degrees. Between 1192 and 1867, the shōguns, or their shikken regents in Kamakura (1203–1333), were the de facto rulers of Japan, although they were nominally appointed by the emperor. After the Meiji Restoration in 1868, the emperor was the embodiment of all sovereign power in the realm, as enshrined in the Meiji Constitution of 1889. Since the enactment of the 1947 constitution, the role of emperor has been relegated to that of a ceremonial head of state without even nominal political powers. The emperor is the head of the Japanese honors system, conferring orders, decorations, medals, and awards in the name of the state and on behalf of its people in accordance with the advice of the Cabinet.

The Kamakura period (鎌倉時代, Kamakura jidai; 1185–1333) is a period of Japanese history that marks the governance by the Kamakura shogunate, officially established in 1192 in Kamakura by the first shōgun Minamoto no Yoritomo after the conclusion of the Genpei War, which saw the struggle between the Taira and Minamoto clans. The period is known for the emergence of the samurai, the warrior caste, and for the establishment of feudalism in Japan.

There are various theories as to the year in which the Kamakura period and Kamakura shogunate began. In the past, the most popular theory was that the year was 1192, when Minamoto no Yoritomo was appointed Seii Taishōgun (征夷大将軍). Later, the prevailing theory was that the year was 1185, when Yoritomo established the Shugo (守護), which controlled military and police power in various regions, and the Jitō (地頭), which was in charge of tax collection and land administration. Japanese history textbooks as of 2016 do not specify a specific year for the beginning of the Kamakura period, as there are various theories about the year the Kamakura shogunate was established.

Sagami Bay (相模湾, Sagami-wan; also known as the Sagami Gulf or Sagami Sea) lies south of Kanagawa Prefecture in Honshu, central Japan, contained within the scope of the Miura Peninsula, in Kanagawa, to the east, the Izu Peninsula, in Shizuoka Prefecture, to the west, and the Shōnan coastline to the north, while the island of Izu Ōshima marks the southern extent of the bay. It lies approximately 40 kilometres (25 mi) southwest of the capital, Tokyo. Cities on the bay include Odawara, Chigasaki, Fujisawa, Hiratsuka, Itō, and Kamakura.

The Miura Peninsula (三浦半島, Miura-hantō) is a peninsula located in Kanagawa, Japan. It lies south of Yokohama and Tokyo and divides Tokyo Bay, to the east, from Sagami Bay, to the west. Cities and towns on the Miura Peninsula include Yokosuka, Miura, Hayama, Zushi, and Kamakura. The northern limit of the peninsula runs from Koshigoe, Kamakura in the west, across to Mt. Enkai, in the southern wards of Yokohama in the east, overlooking Tokyo Bay.

Tsurugaoka Hachimangū (鶴岡八幡宮) is the most important Shinto shrine in the city of Kamakura, Kanagawa Prefecture, Japan. The shrine is a cultural center of the city of Kamakura and serves as the venue of many of its most important festivals with two museums.

For most of its history, it served both as a Hachiman shrine, and in latter years a Tendai Buddhist temple typical of Japanese Buddhist architecture. The famed Buddhist priest Nichiren Daishonin once reputedly visited the shrine to reprimand the kami Hachiman just before his execution at Shichirigahama beach.

The Ashikaga clan (Japanese: 足利氏, Hepburn: Ashikaga-shi; Japanese pronunciation: [a.ɕi̥.kaꜜ.ɡa(.ɕi), -kaꜜ.ŋa(.ɕi)]) was a Japanese samurai clan and dynasty which established the Ashikaga shogunate and ruled Japan from roughly 1333 to 1573. The Ashikaga were descended from a branch of the Minamoto clan, deriving originally from the town of Ashikaga in Shimotsuke Province (modern-day Tochigi Prefecture).

For about a century, the clan was divided in two rival branches, the Kantō Ashikaga, who ruled from Kamakura, and the Kyōto Ashikaga, rulers of Japan. The rivalry ended with the defeat of the first in 1439. The clan had many notable branch clans, including the Hosokawa, Imagawa, Hatakeyama (after 1205), Kira, Shiba, and Hachisuka clans. After the head family of the Minamoto clan died out during the early Kamakura period, the Ashikaga came to style themselves as the head of the Minamoto, co-opting the prestige which came with that name.

Ōe no Hiromoto (大江 広元, 1148–1225) was a Japanese kuge (court noble) and vassal of the Kamakura shogunate, and contributed to establishing the shogunate's governmental structure.