Despite the cultural prominence of the sword, most Japanese pitched battles were settled with pole weapons. The yari — a straight-bladed spear — was the primary battlefield weapon of the Sengoku-period ashigaru, the foot soldiers who made up the bulk of any daimyō's army. The naginata, with its curved sweeping blade, occupied a different niche: the weapon of warrior monks in the medieval period, of senior samurai in particular tactical roles, and later of women of samurai families defending the home.
Yari
The straight-bladed Japanese spear. Yari ranged from short personal weapons of perhaps six feet to massed pike-style weapons exceeding twenty feet, and they were the workhorse battlefield weapon of the Sengoku period (1467–1615). Massed ranks of ashigaru with yari, drilling in coordinated thrust patterns, formed the infantry backbone of every major army of the period — the same kind of solution that European armies arrived at independently with the pike.
Yari heads varied widely. The basic form was the su-yari, a simple straight blade. Specialized forms included the cross-shaped magari-yari (or jumonji-yari) used for catching opposing weapons, and the long-bladed ōmi-yari favored by some elite samurai. Yari shafts were often built up with a hardwood core wrapped in bamboo strips and lacquered, making them surprisingly stiff for their length. By the late Sengoku, the yari was being replaced in primary roles by the matchlock musket — but pikes remained part of Japanese armies through the early Tokugawa period.
Naginata
The curved-bladed Japanese pole-arm. The naginata's sweeping blade — effectively a sword mounted on a long pole — gave it a different tactical character than the straight-thrusting yari. It was a slashing and cutting weapon, capable of long sweeping strokes that worked well against unarmored opponents and against horses' legs. Its origins are debated, but by the late Heian period (12th century) the naginata was firmly established as a weapon of the warrior monks (sōhei) of the great Buddhist temple complexes.
The naginata's role shifted across Japanese history in revealing ways. In the Genpei War (1180–1185), it was a frontline samurai weapon — the legendary warrior-monk Benkei is traditionally depicted with one. In the Sengoku, it was displaced from the battlefield front line by the yari but retained roles in particular tactical contexts. Under the Tokugawa peace, it became closely associated with women of samurai families: the onna-bugeisha trained in naginata for home defense, and the form remained part of women's martial education well into the modern era.