The area of Yamaga was part of ancient
Higo Province. There are many
burial mounds dating from the
Kofun period within the city limitsm and the name "Yamaga" appears in early 8th century records. During the
Kamakura period, the area developed as a
hot spring town and in the
Muromachi period it developed into a commercial settlement and a
post town on the
Buzen Kaido highway, and was noted for its production of umbrellas. During the
Edo Period it was part of the holdings of
Kumamoto Domain. It was the site of a battle during the 1877
Satsuma rebellion. After the
Meiji restoration, the town of Yamaga was established with the creation of the modern municipalities system on April 1, 1889. On January 15, 2005, Yamaga absorbed the towns of
Kahoku,
Kamoto,
Kaō and
Kikuka (all from
Kamoto District) to create the new and expanded city of Yamaga. ==Government==