The vast, vast majority of firearms used in the Sengoku and Edo periods were manufactured in Japan. The Japanese were quick to recognize the power of the arquebus and quickly learned how to make them (Portuguese Goa-type marine arquebus?). At first, a few regions in Japan were responsible for making and exporting the majority of firearms, but soon their method of manufacture spread all through-out Japan. By the closing days of the Sengoku, perhaps a quarter of all front-line troops used firearms, causing the largest number of wounds among all weapon types. And it's use has spread to civilians, who used them for hunting and warding off wild animals.

Their manufacture and use were relatively unchanged in the Edo period (besides the fact there were no wars so the number of frontline troops plummeted). However by the mid nineteenth century, the government and many different clans recognized that their arquebuses were now outdated. In the lead up to the Meiji Restoration, the Bakufu and most influential clans began to spend large amount of sums importing flintlock or percussion cap muskets, rifled-muskets, and the first wide-spread breach-loading rifles like the Spencer repeating rifle/cavalry carbine and the Snider-Enfield conversion of the Enfield rifled-muskets. Though many separate attempts were made to try to manufacture these weapons (mostly rifled-muskets) in Japan, by the outbreak of war, the vast majority of weapons, especially the very small quantities of repeating rifles that made a large impact in the war, would have been bought from European and American traders. Notably many rifled-muskets used in the Boshin War were leftovers from the American Civil War.