Japan's feudal period was defined by constant battles between opposing factions. Although it was a critical time for the region, it also paved the way for new weapons. Japanese bladesmiths invented dozens of bladed weapons throughout this period, some of the most common being the following.
Meaning "long wrapping," the nagamaki is a traditional Japanese sword that featured a single-edge, curved blade with a long handle. It was used extensively throughout Japan's feudal period by samurai warriors, many of whom preferred the nagamaki because of its long handle.
Perhaps the most well-known traditional Japanese sword originating from the region's feudal period is the katana. Also featuring a single-edged, curved blade, the katana has become synonymous with quality swords. It's believed that the katana first appeared sometime during the Kamakura Period (1185 to 1333). Historians regard it as being one of the most significant weapons in Japan's history, as it allowed samurai warriors defend against invading forces, especially the Mongolians during the Mongol Invasions.
Not all bladed weapons invented in feudal Japan were swords. Some were spears, such as the yari. Featuring a tall pole -- typically made of wood -- with one or more spearheads at the tip, the yari allowed samurai warriors to engage enemies while keeping a safe distance. While the yari was a unique weapon, Japanese bladesmiths likely borrowed at least some of the design schematics from Chinese spears.
Also known as the ninjaken or shinobigatana, the ninjato was the preferred sword of Shinobi (ninjas) in feudal Japan. Although it was designed in a variety of configurations, most ninjato featured a single-edge blade with either no or little curvature. It had an average weight of less than 1 pound and a length of about 19 inches (48 cm). Therefore, the ninjato was relatively small when compared to other traditional Japanese swords like the katana and wakizashi.
In addition to the yari, another traditional Japanese bladed weapon that isn't a sword is the bisento. Meaning "brow blade," the bisento is a pole weapon that was invented during feudal Japan. It featured a straight pole with one or more spears at the tip. According to historians, the bisento was used by Shinobi and peasants alike, many of whom preferred it over traditional swords because of its long length and versatility.
These are just a few bladed weapons that were invented during feudal Japan. Japanese bladesmiths produced countless others, most of which were either swords, spears or pole weapons.