After the Korean Expedition of the Empress Zingu (170-269), Japanese armour received influence from the continent as above explained. But from the end of the Asuka Period (592-710), the arms and war tactics of the T'ang Dynasty of China began to be imported.

Oyoroi (great harness) presented to the Emperor of Manchoukuo

It was at about this time that the military class rose to oppose the nobles who bad been the guiding influence of the country. Warriors lived in rural districts, and with their military power they gradually extended their influence to surrounding districts. It was natural that fighting should occur among warriors and so their arms were improved. Japanese swords were forged and bows and arrows made, which were much stronger than those in the past. The development of offensive weapons did not leave armour unchanged. The first requirement of armour was to be strong and fit for practical use. Another notable point was that it must be beautiful, at least for the old Japanese. It was particularly so later, in the Kamakura Period (1185-1392), when the ideal of Busido be-came definitely crystallized. But already in this period, the life of warriors was guided not only by moral principles but also by a sensitiveness to beauty. They had to win in battles above everything else, and therefore they respected military strength. Yet the aesthetic side of their character was in harmony with their military life, though to some it might sound contradictory. Therein lie the characteristics of Busido. The warriors' love of beautiful things and arts was not sentimental or epicurean, but was an important factor through which they cultivated their personality and purified their life. I his thought is reflected in the armour and arms of the period.

Full armoured wooden statue of Date-Masamune, a mediaeval feudal lord, Zuigan-zi Temple, Sendai (16-7th cent.)

How then was the armour of this period made? As materials for armour, small boards or scales of cow-hide were mostly used, and also in some important parts, small iron plates or scales called 1 etuzane (iron scales) were laced together and used. All these were painted with shining black lacquer. The plaited silk braid or chamois leather thongs, lacing together the small scales, were dyed various colours with vegetable dyes obtained from flowers, plants and roots. Furthermore, gold- or silver-plated copper scales were added for practical and ornamental purposes. Thus in the Heian (794-1185) and later periods there appeared suits of armour which were really works of art.
In this period, fighting on horseback with bows and arrows was most common. Therefore military families were called Yumiya-no-ie (families of bows and arrows), and Busi, or warriors, were often named Yumitori (bowmen). In the tales of wars and battles, the strength of a force was expressed in terms of the number of horsemen.
The armour of this period can be classified into the two kinds of Oyoroi (great harness) and Haramaki (simple corselet). Oyoroi was used by generals and others on horseback, but Haramaki was generally for the foot-soldiers.
The first notable point in the construction of Oyoroi is that there are attached at both shoulders flexible lames of scales spreading downward, which are not seen in the armour of other countries. They are called Sode (shoulder protectors). As horsemen used both hands for shooting arrows and could not hold shields at the same time, the Sode developed as a substitute for shields to stop the enemy's arrows and sword-blows. It is attached to the body of the armour by four plaited cords, in a clever way to enable it to move backward and forward.

The Busi class that increased its influence towards the end of the Heian Period (794-1185) established its position firmly in the Kamakura Period. The rivalry between the Minamoto and Taira clans raged fiercely during the former period, but finally the Minamoto won. In the third year of Kenkyu, or 1192, Minamoto-no-Yoritomo was appointed Seiitaisyogun (“Great General for Subjugating the Barbarians”) and thus the Kamakura Bakuhu (military government) was established, laying the foundation of the military rule that continued nearly seven hundred years. The Minamoto family came to ruin after a rule of twenty-eight years, and the Hozyo family took its place and continued the system of military administration.
The Kamakura Period was in a word a period of martial spirit. The warriors of the period, who faithfully followed the spirit of Busido, were honest and sturdy; they valued the morality of loyalty and filial piety, and the principle of relation between superiors and inferiors, and were willing to sacrifice even their life for the sake of justice. Therefore, it was natural that armour, one of the necessary requirements of warriors, made notable developments in the period.

Kuwagata (antlers) came to be widely used at about this time, but is not seen much in the relics of earlier periods. Yet the oldest specimen of antlers now preserved is said to be of a much earlier date. It is the Kuwagata kept at the Seisui-zi Temple, Nagano Prefecture and said to have been presented by Seiitaisyogun (Great General) Sakanoue-no-Tamuramaro (757-810), a great warrior in the early years of the Heian Period (794-1185). But it is now thought that this is of a later period. The Kuwagata are old-fashioned iron antlers and have a design of dragons and clouds inlaid in gold.

Names of the parts of Tosei-gusoku (modern armour)

The origin of Kuwagata is believed to have been an attempt to imitate a deer's antlers. The old form of Kuwagata has a very wide base, so that the whole shape looks like the Kuwa (hoe) of Japanese farmers, and thus the name originated, it is believed. The shape of Kuwagata changed from one age to another but in almost all cases, it was made of copper and generally gold-plated.
It has already been explained that the scale armour of the Heian Period was divided into Oyoroi (great harness) and Haramaki (simple corselet), and that Oyoroi was worn by generals and other mounted warriors and Hara¬maki mainly by foot-soldiers.

Japan was confronted with an unparalleled crisis in the latter ball of the 13th century. The great Mongol Empire that had conquered the major portion of Asia and the eastern section of Europe invaded Japan. Fighting took place twice in the west coast district of the country. Japan, however, with the united efforts of the whole country, and also with the special help of Providence, succeeded in repulsing the enemy. This experience brought significant influences in all military matters.
With this war as the turning point, the method of warfare changed toward the end of the Kamakura Period. The former horseback fighting became unpopular and hand-to-hand fighting became the main battle method. The new tendency was to engage in close fighting with swords and spears instead of using bows and arrows. Thus the former heavy Oyoroi armour fell into disuse and lighter Haramaki armour came into more general use.