[1] In the late Edo period, the Tokugawa shogunate was increasing alarmed by incursions by foreign ships into Japanese territorial waters, fearing that these kurofune warships of the United States or other Western powers would attempt the end Japanese self-imposed national isolation policy by force, or would attempt an invasion of Japan by landing hostile military forces.

The most powerful daimyō of Echizen Domain, Matsudaira Yoshinaga was at the time a hard-line supporter of the sonnō jōi movement, and quickly responded by 26 cannons in several batteries along his coastline in 1848.

In neighboring Wakasa Province, the Sakai clan of Obama Domain was quick to emulate this example, completing these batteries in 1854, the year after the arrival of the Perry Expedition at Uraga.

Matsugase No.1 Battery faced the entrance to the bay, and had five cannons in a row, behind an earthen rampart which extended for 50 meters.

[2] The Kawasaki Battery (川崎台場跡) 35°30′1.4″N 135°44′30.1″E / 35.500389°N 135.741694°E / 35.500389; 135.741694 was built in 1854 and consists of seven locations in the inner bay close to Obama Castle, with mountings for a total of 55 cannon.