長曾祢興里虎徹 Nagasone Okisato Kotetsu

What is Nagasone Okisato Kotetsu in Japanese Katana terminology?

Nagasone Okisato Kotetsu was a swordsmith during the Edo period. Originally an armorer, he is said to have switched from armorer to swordsmith after the age of 50. He is famous for the name "Kotetsu", but he has left inscriptions such as "Kotetsu" and "Kotetsu" depending on the era. Notably, five of his swords have been designated as important cultural properties, all of which bear the inscription "Kotetsu".