The short Japanese bow is commonly called Hankyū. Another name is Tankyū (短弓). These names are generic, and some ryuha may use other names. Hankyū and Tankyū have been coined in reference to the Yumi, which has been the standard bow for Japanese bowmen throughout history. Hankyū means "half bow" and is approximately half the length of the Yumi, ranging between 1 to 1.25 meters in length. Tankyū means "short bow" and also refers to bows that are considerably shorter than 1 meter. The construct of the Hankyū, similar to the long Yumi, have developed over time. Early bows were made of Azusa, Haji, Maki and other types of wood. Later they were made of layers of wood and bamboo in what is called "compound bow."
The arrows were made of wood or bamboo, with bird feathers of various types, but with preference to the sturdy feathers of birds of pray. Arrowheads included mainly the forged iron single-point and the crescent-shape (resembling the Latin letter "Omega") heads, but also the wooden barrel-shaped head called Kabura-ya. The latter was originally designed to emit a distinct whisling sound in flight, but was later used for as a fire arrow, or to deliver explosives or any type of powder.
The Hankyū was short and light, with considerable strength, which could allow the bowman to pass through narrow paths and shoot in tight spaces such as the indoors of a fort or a castle. While the arrow of a Hankyū could reach a target 50 meters or more away from the shooter, in direct aim the arrow is most powerfull in the range of between 5 to 15 meters.
Refference to Hankyū in primay historical records is near to none, and in the very few records that mention Hankyū, it is always in reference to the bows of foreign armies. In the illustrated narrative Kibidaijin nittō emaki, which tells the story of the magical journey of the Minister Kibi of Makibi to China, we can see a Chinese warrior on the seashore waiting for Kibi's ship to arrive, then on a horseback stirring his horse while hoding the short bow. Then, in the illustrated narrative Mōko shūrai ekotoba, which tells the heroic deeds of the Japanese warrior Takezaki Suenaga in defence of Japan from the invading Mongols (1274, 1281), we can view numerous Mongol warriors using short bows.
Both these illustrated narratives were produced in the 13th century, which confirms without doubt that by that time the Japanese were exposed to and fully aware of short-bow warfare. It would also be safe to assume that the Japanese were familiar with short bows already centuries earlier. Yet, there is no indication that there was any change in Japanese bowmanship at any time throught history as a result of this exposure to short bows. Any adoption of the short bow must have been by marginal groups, such as pirates, mountain brigands, or special groups such as those in Kii and Iga. This, needless to say, makes tracing the origin, development and usage of the short bow extremely difficult.
Written records that have any reference to Hankyū or Tankyū are even more difficult to find. In fact, a comprehensive search of tens of thousands of documents from the Nara to Edo periods produced only a single reference. Before the second invasion attempt to the Korean penninsula, Toyotomi Hideyoshi issued instruction to his military to cut their standard immobile wooden shilds to smaller shields and make them personal warrior equipment so that warriors could use them for individual defence as they moved. Hideyoshi stipulates that the enemy is using Hankyū, suggesting that they are more flexible in terms of mobility and space, thus the Japanese warriors need to have a viable defence against the enemy arrows even in places and spaces that were considered safe in Japanese warfare.
An illustrated encyclopedia compiled in the Edo period is probably the only primary source with clear indication that the short bow was a known weapon in the Japanese early-modern arsenal. In this record, the Hankyū is refered to as Wa-Hankyū, or "Japanese half bow." Its illustration is presented in conjunction with a Chinese short bow, indicating that the concept of a short bow is not a Japanese creation but instead an adoptation and adaptation of the Continental bow.
In modern Japan the practice of short bow is limited to only a handfull of ryuha and organizations such as Genbukan and Heki ryu. One can find a number of modern schools that abandoned the old style warfare-like practice, and teach and practice the short bow as "Shihan mato (四半的)" in a style and manner that stripped it of its former character as a weapon of war.
In Genbukan we adhere to tradition and old style usage, focusing on the two primary shooting postures of standing and sitting. In addition we practice fast shooting, shooting in movement, and long and short range, among other styles and variations. The video below illustrates some of these styles and variations.