The Kōyō Gunkan (甲陽軍鑑) is a compendium of Takeda clan’s memoirs, views & practices related to military affairs when they ruled over Kai province (present-day Yamanashi prefecture) during the 1500s. While compiled after the demise of the Takeda family, many sought after its contents as a form of documentation on strategy.
The “Ueno Tamaki Kabunsho” (上野太真記家文書) is a collection of manuscripts and documentations related to those families from Koka who engaged in military affairs in the past. Within this collection is one that is labeled “Heihō Densho (Kōyō Gunkan no naigunpō no maki)” (兵法伝書（甲陽軍鑑之内軍法之巻）), which contains select sections from the actual Kōyō Gunkan. On a fundamental level, these sections appear to have been chosen as a model for the basis on warfare.
For this project, I wanted to compare the contents between both, to see if there are any divergences from the original Kōyō Gunkan to the Ueno Tamaki Kabunsho. Along with this, English translations are provided of these selected sections, just to get a glimpse of the possible methods and formalities used for battlefield during the Sengoku period.
As a reference, I will be using a copy from the National Diet Library Digital Collections. The format for each page will be the following:
- using an image from this version of the Kōyō Gunkan (if any)
- Placing the Japanese text from the Ueno Tamaki Kabunsho next to the image as a comparison
- Stating the reference page from the Kōyō Gunkan were the image was taken (if any)
- English translation of the Japanese text
Keep in mind that there some slight differences in the text from both sources. Whereas the referenced Kōyō Gunkan was published in digital form in 1892, the document mentioned in the Ueno Tamaki Kabunsho that contained those selected sections is said to have been signed and produced in 1742. However, when reproducing those sections in the Ueno Tamaki Kabunsho, there is a note early in the book that mentions the wording from the original text being altered with slight reformatting for ease in reading. Nonetheless the contents of both texts remain the same.