Mutsu Province in the context of "Shimotsuke Province"

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.

Aizu (会津) is the westernmost of the three regions of Fukushima Prefecture, Japan, the other two regions being Nakadōri in the central area of the prefecture and Hamadōri in the east. As of October 1, 2010, it had a population of 291,838. The principal city of the area is Aizuwakamatsu.

It was part of Mutsu Province; the area once was part of Iwase Province created during the reign of Empress Genshō. The Yōrō Ritsuryo established the Iwase Province in 718 through the division of the Michinoku Province (Mutsu Province). It was composed of five districts of Shirakawa (白河), Iwase (石背), Aizu (会津), Asaka (安積) and Shinobu (信夫). The area encompassed by the province reverted to Mutsu some time between 722 and 724.

Aomori Prefecture (青森県, Aomori-ken; Japanese pronunciation: [a.oꜜ.mo.ɾʲi, a.o.mo.ɾʲiꜜ.keɴ]) is a prefecture of Japan in the Tōhoku region. The prefecture's capital, largest city, and namesake is the city of Aomori. Aomori is the northernmost prefecture on Japan's main island, Honshu, and is bordered by the Pacific Ocean to the east, Iwate Prefecture to the southeast, Akita Prefecture to the southwest, the Sea of Japan to the west, and Hokkaido across the Tsugaru Strait to the north. Aomori Prefecture is the eighth-largest prefecture, with an area of 9,645.64 km (3,724.20 sq mi), and the 31st-most populous prefecture, with more than 1.18 million people. Mount Iwaki, an active stratovolcano, is the prefecture's highest point, at 1,624.7 m (5,330 ft).

Humans have inhabited the prefecture for at least 15,000 years, and the oldest evidence of pottery in Japan was discovered at the Jōmon period Ōdai Yamamoto I Site. After centuries of rule by the Nanbu and Tsugaru clans, the prefecture was formed out of the northern part of Mutsu Province during the Meiji Restoration in the 19th century. The entire Tōhoku region, including Aomori Prefecture, experienced significant growth in population and economy until the late 20th century, when a significant population decline began. Though the prefecture remains dominated by primary sector industries, especially apple orchards, it also serves as a transportation and logistics hub due to its location. Additionally, it is the largest producer of black garlic in Japan. Tourism is also a significant part of the prefecture's economy, especially due to the Jōmon Prehistoric Sites in Northern Japan and Shirakami-Sanchi World Heritage Sites.

The Battle of Ōshū (奥州合戦, Ōshū-kassen) was a major battle between the Kamakura government and the Northern Fujiwara that took place in the Tōhoku region of Japan from September 1 to October 14, 1189. It resulted in the downfall of the Northern Fujiwara and the completion of Minamoto no Yoritomo's nationwide domination through the annexation of Mutsu and Dewa Province by the Kamakura shogunate. It was the last battle of the period of civil war known as the Jishō-Juei War that began in 1180, and its end marked the establishment of the first military government, the Kamakura shogunate.

The Kunohe rebellion (九戸政実の乱, Kunoe Masazane no Ran) was an insurrection of the Sengoku period of Japan that occurred in Mutsu Province from 13 March to 4 September 1591. The Kunohe Rebellion was the final battle in Toyotomi Hideyoshi's campaigns during the Sengoku period and completed the unification of Japan.

Hitachi Province (常陸国, Hitachi no Kuni; Japanese pronunciation: [çi̥ꜜ.ta.tɕi (no kɯ.ɲi), çi̥.taꜜ.tɕi-]) was an old province of Japan in the area of Ibaraki Prefecture. It was sometimes called Jōshū (常州). Hitachi Province bordered on Shimōsa (Lower Fusa), Shimotsuke, and Mutsu (Iwase -1718-, Iwashiro -1869-, Iwaki -1718- and -1869-) Provinces. Generally, its northern border was with Mutsu.

Dewa Province (出羽国, Dewa no Kuni; Japanese pronunciation: [deꜜ.wa (no kɯ.ɲi)]) was a province of Japan comprising modern-day Yamagata Prefecture and Akita Prefecture, except for the city of Kazuno and the town of Kosaka. Dewa bordered on Mutsu and Echigō Provinces. Its abbreviated form name was Ushū (羽州).

The Nanbu clan (南部氏, Nanbu-shi) was a Japanese samurai clan who ruled most of northeastern Honshū in the Tōhoku region of Japan for over 700 years, from the Kamakura period through the Meiji Restoration of 1868. The Nanbu claimed descent from the Seiwa Genji of Kai Province and were thus related to the Takeda clan. The clan moved its seat from Kai to Mutsu Province in the early Muromachi period, and were confirmed as daimyō of Morioka Domain under the Edo-period Tokugawa shogunate. The domain was in constant conflict with neighboring Hirosaki Domain, whose ruling Tsugaru clan were once Nanbu retainers.

During the Boshin War of 1868–69, the Nanbu clan fought on the side of the Ōuetsu Reppan Dōmei, supporting the Tokugawa regime. After the Meiji Restoration, the Nanbu clan had much of its land confiscated, and in 1871, the heads of its branches were relieved of office. In the Meiji period, the former daimyō became part of the kazoku peerage, with Nanbu Toshiyuki receiving the title of hakushaku (count). The main Nanbu line survives to the present day; Toshiaki Nanbu served as the chief priest of Yasukuni Shrine.