The area of Kaminoseki was part of an ancient
Suō Province. From the
Heian period, it was the location of a maritime checkpoint to control trade and traffic in the Seto Inland Sea and until the end of the
Muromachi period was called "Kamadoseki". Also during the Muromachi period, it was a noted base for
Wokou pirates who raided the coasts of China and Korea. During the
Edo Period, the area was part of the holdings of
Chōshū Domain and prospered as a port for the
kitamaebune coastal trade. Following the
Meiji restoration, the village of Kaminoseki within
Kumage District, Yamaguchi was established with the creation of the modern municipalities system on April 1, 1889. Kaminoseki annexed the neighboring village of Murotsu and was elevated to town status on February 1, 1958. ==Government==