Gunma Prefecture (群馬県, Gunma-ken) is a prefecture of Japan located in the northwest corner of the Kantō region on the main Honshu island. Its capital is Maebashi.
Japan was without horses until around the fifth century CE. The ancient province of Gunma was a center of the horsebreeding and trading activities for the newly immigrated continental peoples. The arrival of horses and the remains of horse-tackle coincides with the arrival of a large migration from the mainland. From this point forward, the horse became a vital part of Japanese military maneuvers, quickly displacing the older Yayoi tradition of fighting on foot.
When Mount Haruna erupted in the late 6th century, Japan was still in the pre-historical phase (prior to the importation of the Chinese writing system during the Nara period). The Gunma Prefectural archaeology unit in 1994 was able to date the eruption through zoological anthropology at the corral sites that were buried in ash.
In the past, Gunma was joined with Tochigi Prefecture and called Kenu Province. This was later divided into Kami-tsu-ke (Upper Kenu, Gunma) and Shimo-tsu-ke (Lower Kenu, Tochigi). The area is sometimes referred to as Jomo (上毛, Jōmō). For most of Japanese history, Gunma was known as the province of Kozuke.
Gunma is the name of several places in Japan:
In Gunma prefecture: