Beginning in 1641, the Edo Government put the Saga Donain and Fukuoka Domain in charge of guarding Nagasaki in alternative years. But the defences were very poor compared with those of other nations, Nabeshima Naomasa, the 10th lord of Saga, proposed a plan to reinforce the defences.

The government turned it down, however, Naomasa, who was interested in Western Learning, built a Western-style reverberatory furance here in 1850 at his own expense and set up the Tsukiji Cannon Factory, which produced cannon for the defense of Nagasaki's fort.