I gleaned further Information on the original inquiry of this post.From the Japan Patent Attorneys Association-"Nobunaga oda, a powerful warlord who rose to ascendancy in 16th century Japan,used muskets as an effective weapon in his bid to reunify the nation.The first musket was introduced to Japan in 1543 by a Portuguese Castaway whose ship was stranded(1542)on Tanegashima Island,off Kyushu.At that time,Japan was in the middle of the Sengoku period, and provincial warlords threw themselves into a fierce race to obtain this powerful weapon(Teppo).As a result,the modern technology of musket manufacturing quickly spread throughout Japan.The speed of the spread of this technology was breathtaking,enough to surprise the Portuguese,who came back to Japan two years later to witness the mass production of at Osaka,Sakai and other areas.This indicates that metal working technology used in japanese sword making was already fairly advanced and was readily applicable to musket production,as can be seen from the overlapping of production centers of swords and muskets.As a result of the fierce competition between warlords to obtain this epoch-making new weapon,Japan became one of the leading musket production countries in the world.This however had little impact on other aspects of life in Japan,as the technology acquired through the arrival of the musket was kept under wraps by warlords as their top military secret instead of being turned into public knowledge."From Kyushu tourism-"Tanegashemia Island-The first gun seen in Japan was a musket that a Portuguese sailor brought ashore in Tanegashemia in 1543.A Portuguese musket and the first gun ever made in Japan are among exhibits at a museum in Nishino-omote,a city in the north of the Island." :hmm: