The Type 98 Light Tank (Ke-Ni) was developed as the successor to the Japanese Army’s primary light tank, the Type 95 Light Tank (Ha-Gō). Conceptualized in 1938 with the first prototypes appearing in late 1939, the Type 98 Light Tank was a significant improvement over its predecessor in every respect. It featured thicker armor, a lower profile, a more effective two-man turret, and a coaxial machine gun complementing its main armament. Despite these advantages, the Type 95 Light Tank would remain the only Japanese light tank deployed overseas, seeing widespread combat during the Pacific War.
The Type 98 Light Tank only entered “mass” production in 1942 due to a somewhat protracted development process, but more-so because of a lack of strategic impetus. The existing Type 95 was producing satisfactory results in its infantry-support role in the invasion of China, and with the initiation of the Pacific War, the Army’s production priority for tanks plummeted relative to aircraft, cannons, and infantry equipment. It’s difficult to say that this was a poor decision.
The production priority of tanks would not rise until 1945 in anticipation of the defense of the Japanese home islands, by which point Japan’s capability to produce weapons was deteriorated, and the production of new light tanks in general had ceased in favor of more powerful vehicles to counter Allied armor.

Another forty-two were in a less complete state.
The production run of the Type 98 Light Tank, by essentially all post-war accounts, amounted to over 100 complete vehicles. For example, in Japanese Tanks by Takeuchi Akira & Hara Tomio, it is written that “From 1942 to 1943, 100 vehicles or more were produced, and were deployed to newly established units.” Western historian Steven Zaloga wrote in Japanese Tanks 1939-1945 that 104 vehicles were completed. US technical intelligence, in postwar reporting on Japanese armor, similarly stated that “It is believed that slightly more than 100 of these tanks were completed.”
As an indication for the “general understanding”, at the time this article was written, the English Wikipedia page on the tank cites the 104 figure, and the Japanese page states 113.
There is nothing peculiar about these claims. This general figure of “about 100” is a consensus that originates from primary documents compiled by the US Strategic Bombing Survey’s investigation into Japanese ordnance production immediately after the war. However, closer examination of these postwar records, along with surviving wartime documents, reveals that the actual quantity of production vehicles was far lower than what is widely accepted.
The Origin of the “100” Figure
Following the surrender of Japan on August 15th, 1945, the US Strategic Bombing Survey launched a thorough investigation into Japanese ordnance production during the war. The USSBS ordered tabulated production results from the Army Ordnance Administrative Headquarters, which oversaw the development, production, and supply of ordnance. Below the Administrative Headquarters was the Army Arsenals, each of which oversaw the production of ordnance at their own facilities and subservient civilian factories.
In the days immediately following the announcement of Japan’s surrender, many documents were burned on high orders before their preservation was enforced by the US. Many were also lost to the effects of strategic bombing before Japan had surrendered. Even without considering the destruction of records, it is indicated that the production recordkeeping by the Ordnance Administrative Headquarters and the arsenals subservient to it were often imprecise at any detail finer than yearly, as noted in one report:
The Army Ordnance Bureau and the arsenals kept most of their output records for bookkeeping purposes rather than to follow production closely, and they had a tendency to enter production from the preceding months in the fiscal records of the last 2 or 3 months of the fiscal year. Then they would slacken up on their bookkeeping entries for the first 1 or 2 months of the new fiscal year. This practice tends to overemphasize the disparity between output in March, the last month in the fiscal year, and April, the first month in the fiscal year.
This led to a situation where, rather than being able to refer to accurate records, the relevant organizations had to piece together estimates of monthly production counts after the war from sparse, imprecise data. As a result, there were not many cases where the monthly production counts were anything more than estimates or even just pure guesswork. Nonetheless, these production investigations were carried out at the level of the Army Ordnance Administrative Headquarters and at the level of each arsenal.
The Army Ordnance Administrative Headquarters Investigation
On November 3rd, 1945, the Army Ordnance Administrative Headquarters submitted the first monthly production count of the fiscal years 1941 to 1945, titled「昭和一九四一~一九四五年 兵器生産状況調査表」[1941~1945 Ordnance Production Status Investigation Charts]. This document was not precise, generalizing several types of vehicles into one, and did not even include the Type 98 Light Tank.
Subsequently, a revised version of this document with much more precision was submitted on the 15th of November by the HQ, titled「昭和十六~二十年 月別兵器生産状況調査表」[1941~1945 Monthly Ordnance Production Status Investigation Charts]. The production of the Type 98 Light Tank in this document was recorded as follows:
Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Jan | Feb | Mar | Total | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
FY1942 | 5 | 7 | 2 | 3 | 3 | 2 | 2 | 24 | |||||
FY1943 | 6 | 5 | 6 | 5 | 6 | 5 | 8 | 4 | 7 | 10 | 12 | 15 | 89 |
Total | 113 |
This document is the origin of the figure “113“. Now let’s look at the production investigation charts submitted by the Sagami Army Arsenal itself, which directly oversaw the grand majority of tank production during the Pacific War.
The Sagami Army Arsenal Investigation
The Sagami Army Arsenal submitted the English document “Production Chart of Vehicles with Catapillar by Mfg Plants in 1941~1945” [sic] on November 17th, 1945.
Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Jan | Feb | Mar | Total | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
FY1941 | 1 | 1 | |||||||||||
FY1942 | 5 | 7 | 2 | 3 | 5 | 2 | 24 | ||||||
FY1943 | (2) | (12) | (41) | (7) | (4) | 3 | 4 | 6 | 13+(66) | ||||
Total | 38 + (66) = 104 |
The 38 vehicles without parenthesis were listed as “M98 Light Tank” and were produced by Mitsubishi Heavy Industries, Hino Heavy Industries, Kobe Steel Works, and the Sagami Arsenal itself. It should be noted that the additional 66 units listed with parenthesis added by myself are written in the document as “M98 Light Tank (Repair)” and were all carried out by the Sagami Arsenal.
It seems that the origin of the figure “104” is the assumption that “M98 Light Tank (Repair)” was a typo for what was actually 66 newly produced Type 98 Light Tanks. This even appears to be a sensible conclusion on the surface, as there were not 66 Type 98 Light Tanks in existence to “repair” during that period, it would seem to fill in a strange gap in the production record, and it brings the total production count somewhat in-line with the figure reported by the Ordnance Administrative HQ (113).
Problems with the Established Figures
Of these two sources of production counts detailed above, the easiest to dispel is the notion that the Sagami Army Arsenal recorded the production of 104 Type 98 Light Tanks.
While the entry “M98 Light Tank (Repair)” was indeed a typo, it was not a typo that would create a production tally of 104 for the Type 98 Light Tank. Rather, the original Japanese manuscript that was created on November 10th, 1945 lists these vehicles as 「八九式軽戦車(修理)」[Type 89 Light Tank (Repair)].


This work carried out at the Sagami Arsenal in 1943 was not the repair, much less construction, of 66 Type 98 Light Tanks. It was the repair of 66 Type 89 Light Tanks, or what was more appropriately known as the Type 89 Medium Tank (I-Gō) at that time. (The Type 89 was once a light tank, but was redesignated as a medium tank in 1935).
This means that what the Sagami Arsenal actually reported in its investigation was the production of only 38 Type 98 Light Tanks – 1 in FY1941, 24 in FY1942, and 13 in FY1943. Going forward, we will not be considering the single unit built in FY1941, as this was a prototype, and I do not hope to solve the question of “how many Ke-Ni prototypes were made” in this article.
Both the Sagami Arsenal and Ord Admin HQ investigations agree that 24 of the Type 98 were produced in fiscal year 1942. We can confirm the legitimacy of this figure with a surviving document that recorded the year’s production of ordnance in fiscal year 1942, which was published on March 31st, 1943, titled「昭和十七年度主要兵器整備状況調査表」[FY1942 Major Ordnance Production Status Investigation Table]. This document was reprinted in Senshi Sōsho Volume 33.

Senshi Sōsho 033, p.588
Thus we can be quite confident that the total production of the Type 98 in fiscal year 1942 amounted to 24 vehicles.
The discrepancy that remains is now just fiscal year 1943, where Sagami’s investigation reported 13 tanks completed, but the Ord Admin HQ’s investigation reported a far more substantial 89. Luckily, there is another surviving document which clears the air on which of these counts is more reliable.
A table created by the Sagami Army Arsenal on February 4th, 1944 titled「完成車両整備現況表」[Complete Vehicles Production Status Table] details the production status of the Type 98 Light Tank in FY1943 quite clearly.

This document reveals that 15 Type 98 Light Tanks (labeled “98/Se-K (Light)”, their arsenal designation) were completed in fiscal year 1943, with no more anticipated before the year’s end. The number ordered for that year had been 80, while a total of 96 were arranged for (16 that were not completed the previous year were carried over), making the production shortage for this year 81 vehicles.
15 vehicles produced in 1943 is very close to the arsenal’s postwar count of 13, but how did the Army Ordnance Administrative Headquarters arrive at such a grossly incorrect tally of 89? I have determined that this mistake was a simple oversight related to how the in-house production at the Sagami Army Arsenal was recorded.
In 1942, the Sagami Arsenal reported their production of vehicles in this incidence:
- Type 97 Medium Tank
- Type 98 Light Tank
- Type 98 6t Tractor
- ……
Subsequently, in 1943, there was no production of the Type 98 Light Tank in-house at the Sagami Arsenal itself, and I believe that when tabulating Sagami’s data, the Ord Admin HQ mistakenly counted that year’s production of the Type 98 6t Tractor within the arsenal as a “Type 98 Light Tank”.
Sagami Arsenal reported the completion of 74 Type 98 6t Tractors in 1943. If we remove 74 vehicles from the Admin HQ’s postwar count, we get 15 Type 98 light tanks completed in 1943 – which is in perfect agreement with the wartime document created by Sagami.
Loose Ends
A handful of prototypes of the Ke-Ni were naturally also completed (at least 3), which I plan to investigate in a more comprehensive article on the Type 98 (if I do ever manage to write something again).

There is evidence that the Type 98 Light Tank was planned to be produced in some quantity by the Kokura Arsenal, and the production numbers 2001~3000 were allocated, but I have not found substantial evidence that the Kokura Arsenal actually produced any vehicles in the end.
Conclusion
The long-accepted statement that over 100 Type 98 Light Tanks were produced is a myth caused by clerical errors in the confused aftermath of the war. Evidence definitively shows that the production run of this tank from 1942 to 1943 only amounted to a mere 39 vehicles.
The breakdown is as follows:
- FY1942: 40 vehicles were ordered, split between the Sagami Arsenal itself, and subservient civilian factories of Mitsubishi Heavy Industries, Hino Heavy Industries, and Kobe Steel Works.
- 24 vehicles were actually completed.
- FY1943: 80 vehicles were ordered, and 16 incomplete orders were carried over from the previous year, split between the Sagami Arsenal itself, and subservient civilian factories of Mitsubishi Heavy Industries and Kobe Steel Works (Hino was no longer producing this vehicle).
- 15 vehicles were actually completed.
After this, production shifted to the Type 2 Light Tank (Ke-To) solely under the responsibility of Kobe Steel Works, but this is another can of worms that I do not wish to open just yet.

The Type 98 Light Tank was hardly a vehicle that saw limited mass production, but one that barely entered production at all. What was a capable design when developed was ultimately sidelined by the Japanese Army’s shifting strategic priorities, with the focus falling on the mass deployment of existing capabilities. Tanks, in general, were a lesser concern for island warfare. The Type 98 Light Tank would not see combat, and all examples were deployed within the Japanese home islands when the war ended.

Incidentally, after the war, a total of 39 Type 98 Light Tanks appear to have been accounted for in the US Eighth Army occupation zone.
Sources
- 作業課長会同に関する書類綴(2分冊の2) 昭和19年2月
- 17.造兵廠現況説明/作業課長会同提出書類 相模陸軍造兵廠 昭和19年2月6日(2)
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- 高崎正男『戦史叢書第033巻 陸軍軍需動員<2>実施編』(1970)
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- Zaloga, Steven. Japanese Tanks 1939-1945. Osprey Publishing (2007)