High Quality Content by WIKIPEDIA articles! Yari is the Japanese term for spear, or more specifically, the straight-headed spear. The martial art of wielding the yari is called s jutsu. A Yari can range in length from one meter to upwards of six meters (3.3 to 20 feet). The longer versions were called mi no yari while shorter ones were known as mochi yari or tae yari. The longest versions were carried by foot troops (ashigaru), while samurai usually carried a shorter yari. Yari are believed to have been derived from Chinese spears, and while they were present in early Japan's history they did not become popular until the thirteenth 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 and sword duels.