Yari

Yari (槍^?) is the term for one of the traditionally made Japanese blades in the form of a spear, or more specifically, the straight-headed spear. The martial art of wielding the yari is called sōjutsu.

Early yari are believed to have been derived from Chinese spears, these hoko yari are thought to be from the Nara period (710-794)., and while they were present in early Japan's history, the term yari appeared for the first time in written sources in 1334 but this type of spear did not become popular until the late 15th century. The original warfare of the bushi was not a thing for commoners; it was a ritualized combat usually between two warriors who would challenge each other via horseback archery. However, the attempted Mongol invasions of Japan in 1274 and 1281 changed Japanese weaponry and warfare. The Mongols employed Chinese and Korean footmen wielding long pikes and fought in tight formations. They moved in large units to stave off cavalry. Polearms (including naginata and yari) were of much greater military use than swords, due to their significantly longer reach, lighter weight per unit length (though overall a polearm would be fairly hefty), and their great piercing ability. Swords in a full battle situation were therefore relegated to emergency sidearm status from the Heian through the Muromachi periods. Around the latter half of the 16th century, ashigaru holding pikes (nagae yari) with length of 4.5 to 6.5 m (15 to 21 ft) became the main forces in armies. They formed lines, combined with soldiers bearing firearms (tanegashima (Japanese matchlock)) and short spears. Pikemen formed a two or three row line, and were trained to move their pikes in unison under command.

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