Tōhoku region in the context of "Yamagata Prefecture"

Japan is often divided into regions, each containing one or more of the country's 47 prefectures at large. Sometimes, they are referred to as "blocs" (ブロック, burokku), or "regional blocs" (地域ブロック, chiiki burokku) as opposed to more granular regional divisions. They are not official administrative units, though they have been used by government officials for statistical and other purposes since 1905. They are widely used in, for example, maps, geography textbooks, and weather reports, and many businesses and institutions use their home regions in their names as well, for example Kyushu National Museum, Kinki Nippon Railway, Chūgoku Bank, and Tōhoku University.

One common division groups the prefectures into eight regions. In this arrangement, of the four main islands of Japan, Hokkaidō, Honshu, Shikoku, and Kyūshū, each form their own region, with Kyūshū also including the Satsunan Islands. The largest island, Honshū, is split into five regions. Okinawa Prefecture is usually considered part of Kyūshū, but it is sometimes treated as its own ninth region.

Aizu Domain (会津藩, Aizu-han) was a domain of the Tokugawa Shogunate of Japan during the Edo period from 1601 to 1871.

The Aizu Domain was based at Tsuruga Castle in Mutsu Province, the core of the modern city of Aizuwakamatsu, located in the Tōhoku region of the island of Honshu. The Aizu Domain was ruled for most of its existence by the shinpan daimyō of the Aizu-Matsudaira clan, a local cadet branch of the ruling Tokugawa clan, but was briefly ruled by the tozama daimyō of the Gamō and Katō clans. The Aizu Domain was assessed under the Kokudaka system with a peak value of 919,000 koku, but this was reduced to 230,000 koku. The Aizu Domain was dissolved in the abolition of the han system in 1871 by the Meiji government and its territory was absorbed into Fukushima Prefecture, covering much of the traditional region of Aizu.

The Northeastern Japan Arc, also Northeastern Honshū Arc, is an island arc on the Pacific Ring of Fire. The arc runs north to south along the Tōhoku region of Honshū, Japan. It is the result of the subduction of the Pacific plate underneath the Okhotsk plate at the Japan Trench. The southern end of the arc converges with the Southwestern Japan Arc and the Izu–Bonin–Mariana Arc at the Fossa Magna (ja) at the east end of the Itoigawa-Shizuoka Tectonic Line (ITIL). This is the geologic border between eastern and western Honshū. Mount Fuji is at the point where these three arcs meet. To the north, the Northeastern Japan arc extends through the Oshima Peninsula of Hokkaidō. The arc converges in a collision zone with the Sakhalin Island Arc and the Kuril Island Arc in the volcanic Ishikari Mountains of central Hokkaidō. This collision formed the Teshio and Yūbari Mountains.

The Ōu Mountains form the backbone of the volcanic part of the inner arc that run from Natsudomari Peninsula in Aomori Prefecture south to Mount Nikkō-Shirane in Tochigi and Gunma prefectures. The volcanic front consists of four north to south lines of Quaternary volcanoes and calderas, which extend the length of the range. It also includes the Quaternary volcanoes of southwestern Hokkaido. The Dewa Mountains and the Iide Mountains are non-volcanic uplift ranges that run parallel to the west of the Ōu Mountains.

The Genpei War (源平合戦, Genpei Kassen, Genpei-Gassen; 1180–1185) was a national civil war between the Taira and Minamoto clans during the late Heian period of Japan. It resulted in the downfall of the Taira and the establishment of the Kamakura shogunate under Minamoto no Yoritomo, who appointed himself as Shōgun in 1192, governing Japan as a military dictator from the eastern city of Kamakura.

It followed a coup d'état by the Taira in 1179 with the removal of rivals from all government posts, and subsequently banishing them, and a call to arms against the Taira, led by the Minamoto in 1180. The ensuing Battle of Uji took place just outside Kyoto, starting a five-year-long war, concluding with a decisive Minamoto victory in the naval Battle of Dan-no-ura. However, it has been pointed out that the Battle of Ōshū in 1189 was the last battle during this period of civil war, as it completed Yoritomo's nationwide domination through the annexation of Northeast Japan.

Fukushima Prefecture (福島県, Fukushima-ken; Japanese pronunciation: [ɸɯ̥.kɯꜜ.ɕi.ma, -kɯ.ɕi.maꜜ.keɴ]) is a prefecture of Japan located in the Tōhoku region of Honshu. Fukushima Prefecture has a population of 1,771,100 (as of 1 July 2023) and has a geographic area of 13,783.90 square kilometres (5,321.99 sq mi). Fukushima Prefecture borders Miyagi Prefecture and Yamagata Prefecture to the north, Niigata Prefecture to the west, Gunma Prefecture to the southwest, and Tochigi Prefecture and Ibaraki Prefecture to the south.

Fukushima is the capital and Iwaki is the largest city of Fukushima Prefecture, with other major cities including Kōriyama, Aizuwakamatsu, and Sukagawa. Fukushima Prefecture is located on Japan's eastern Pacific coast at the southernmost part of the Tōhoku region, and is home to Lake Inawashiro, the fourth-largest lake in Japan. Fukushima Prefecture is the third-largest prefecture of Japan (after Hokkaido and Iwate Prefecture) and divided by mountain ranges into the three regions of Aizu, Nakadōri, and Hamadōri.

Tōsandō (東山道; Japanese pronunciation: [toː.saꜜn.doː, toꜜː.san.doː], lit. 'Eastern Mountain Circuit') is a Japanese geographical term. It means both an ancient division of the country and the main road running through it. It is part of the Gokishichidō system. It was situated along the central mountains of northern Honshu, specifically the Tōhoku region.

This term also refers to a series of roads that connected the capitals (国府, kokufu) of each of the provinces that made up the region.

Mutsu Province (陸奥国, Mutsu no Kuni; Japanese pronunciation: [mɯꜜ.tsɯ (no kɯ.ɲi)]) was an old province of Japan in the area of Fukushima, Miyagi, Iwate and Aomori Prefectures and the municipalities of Kazuno and Kosaka in Akita Prefecture.

Mutsu Province is also known as Ōshū (奥州) or Michinoku (陸奥 or 道奥). The term Ōu (奥羽) is often used to refer to the combined area of Mutsu and the neighboring province Dewa, which together make up the entire Tōhoku region.

The Northern Fujiwara (奥州藤原氏 Ōshū Fujiwara-shi) were a Japanese noble family that ruled the Tōhoku region (the northeast of Honshū) of Japan during the 12th century, 1094-1104, as their own realm.

They succeeded the semi-independent Emishi families of the 11th century, who were gradually brought down by the Minamoto clan loyal to the Imperial Court in Kyoto. They ruled over an independent region that derived its wealth from gold mining, horse-trading and as middlemen in the trade in luxury items from continental Asian states and from the far northern Emishi and Ainu people. They were able to keep their independence vis-a-vis Kyoto by the strength of their warrior bands until they were ultimately conquered by the Kantō samurai clans led by Minamoto no Yoritomo, in the Battle of Ōshū in 1189.

The Okhotsk plate is a minor tectonic plate covering the Kamchatka Peninsula, Magadan Oblast, and Sakhalin Island of Russia; Hokkaido, Kantō and Tōhoku regions of Japan; the Sea of Okhotsk, as well as the disputed Kuril Islands.

Japan's principal fault system is the zone where the Amur plate, the Eastern edge of the Eurasian plate, meets the Okhotsk plate, sometimes considered the Western edge of the North American plate.