Bansenshukai

"Military craft is incredibly deep and vast and it is not a matter to be taken lightly" - Fujibayashi Sabuji

Bansenshukai diagram about the use of divination and esoteric cosmology (onmyōdō) to instruct on the ideal time for taking certain actions.

Bansenshukai (萬川集海, translated "Sea of Myriad Rivers Merging" or "A Myriad of Rivers Merging into One Ocean") is a Japanese scroll containing a collection of knowledge from the Iga clans that had been devoted to shinobi no jutsu. It was happily shared with Koka-mono in an attempt to stop the arts of the shinobi from slipping out of history. It has been claimed that the Bansenshukai was also not available for public viewing until the mid-twentieth century due to its dangerous nature.

According to the researcher Mr Ikeda of Iga, there are Iga families who claim that the correct name is the Mansenshukai. It is impossible to establish if this is a regional difference – being Mansenshukai for the Iga and Bansenshukai for the Koka – owing to the contamination of modern research and communications networks between enthusiasts, who may have swayed the opinions of the families on the naming of the manual.

It consisted of ten books, which were divided into twenty-two volumes, with a later additional volume titled Bansenshukai Gunyo-hiki, which is a collection of military strategies. This complete collection of books appears to have been put together by the author after extensive research and information-collecting from other families and clans in the region who also held the arts of shinobi no jutsu. From here multiple transcriptions appear, with slight variations, including examples of reduced versions.

It was compiled by Fujibayashi Sabuji, who was probably of Iga and from a former samurai family, in 1676, in the early years of the Tokugawa shogunate, to preserve the knowledge that had been developed during the near-constant military conflict from the Ōnin War until the end of the Siege of Osaka almost 150 years later. Some Koka-mono traveled the distance to Edo to appeal to the shogunate in the hope of recovering their status by offering them the Bansenshukai manual in 1789. To their disappointment, however, their appeal was not accepted.

Bansenshukai collapsible ladder

As well as information on military strategy and weapons, the manual has sections on the astrological and philosophical beliefs of the times, and along with the Shoninki of 1681 and the Shinobi Hiden of 1655 make up the three major sources of direct information about the arts of the shinobi. A number of transcriptions of the Bansenshukai have been left and, as they were all transcribed by hand and not mechanically, no two transcriptions are completely identical in terms of extra snippets found here and there in the body, or extra volumes.

After World War II, a limited number of hand written copies were offered to the public. A few of these copies are in some major national and university libraries while some versions of the manual exist in private collections in Iga. Some of these have not yet been identified and cataloged. Yamanaka Tonai swore an oath of secrecy to Ohara Kazuma and Ueno Tamaki in order to obtain an extract of the first few books of the Bansenshukai. It has recently been re-translated in various languages including English, French, German, and Japanese.

Known Translations

• Ohara Kazuma version – National Archives of Japan
• Fujita Seiko version – Iga Ueno Museum
• Okimori version – Iga Ueno Museum
• Yamaga excerpt – Tokyo University
• Ohara (Katsui) of Kyoto version- entrusted to the Koka Ninja Village (tourist attraction) from their private collection
• Osawa version – Private Collection
• Taki version – Private Collection
• Sawamura version – Private Collection
• Ohara Kazuma version - Private Collection of the Ohara family of Koka

Contents

"If you have myriad strategies but do not have ninjutsu or the arts of the ninja, then in this case you will not be able to obtain details about the enemy’s secret plan or their conspiracies" - Fujibayashi Sabuji

• Two Volumes of beliefs and philosophy - Full of references to Chinese events, all of which are there simply to highlight the truth of what he is saying and to reinforce his ideas in the minds of the educated reader
• Four Volumes on management
• Three Volumes on Yo-nin - open disguise
• Five Volumes on In-nin - hidden infiltration
• Two Volumes on astrology (Methods of establishing if a direction, day or time is favorable or not. Fujibayashi himself states that these skills are dubious and not to be trusted. The skills themselves were forms of divination that were standard among Japanese generals and well understood to be Chinese teachings. Therefore, the two major Chinese sections are openly acknowledged as such and are loaded with the warning that these practices are not to be trusted, but that the knowledge of them is useful when conducting warfare against a general who does believe in their supernatural power)
• Five Volumes on equipment and weapons - Fujibayashi comments on the newness of some of the tools, indicating that they are Japanese