Leland Ness book and the trench mortar battalions

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Joan Pinyol
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Leland Ness book and the trench mortar battalions

#1

Post by Joan Pinyol » 10 Sep 2014, 00:04

Finally, a couple of days ago, I received from Amazon a copy of the Leland Ness' new book (I ordered it in april). After a first glance, i must to coincide with Mr. Wellgunde: it is not an order of battle. There are a lot of work and effort, particularly on the TOE of infantry and artillery units. It is, no doubt, a big step ahead in the research, but it is not an order of battle.
But, let me left the literary comments, to highlight one topic amongst the many that the book suggests: the trench mortar battalions or (as in this forum we usually call them) the infantry mortar battalions: in the page 242, Leland Ness explained: "in March 1945 IGQH activated the 23rd and 25th trench mortar battalions, followed in May by the 24th and the 26th-40th trench mortar battalions, all in Japan for the defence of the homeland". In the same page, two paragraphs below, Leland Ness pointed out a second raising of 1st to 32nd trench mortar battalions by an Army Regulation issued on May 23rd, 1945., the same day of the group of 26th-40th formerly quoted. I checked my notes and a 4 year ago topic in this forum, with excellent contributions of Mr. Akira Takizawa and Mr. Fontessa (http://forum.axishistory.com/viewtopic. ... 5&t=182576). I concluded that the 23rd-32nd battalions of the first group and the 23rd-32nd battalions of the second group are the same. Perhaps I am wrong, but I only found one trench battalion from 23rd to 32nd in Mutumi Encyclopaedia final position, in the demobilization reports, e.c.

On the other hand, the 20th. There are one 20th assigned to Ogasawara Fortress Corps, CO Captain Mitsuo Mizuashi, formed in April 1944 (or June). And there are another 20th assigned to the 57th Army in Japan (I don't know its CO). Perhaps this second 20th was formed after the first was disbanded in Iwo Jima in March 1945?

And finally, What happened with the 22nd, according with my notes in the 13th Army in China (CO: Tatsuji Motoda)? It not appears in Leland Ness book.

Thanks a lot for your comments and suggestions

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hisashi
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Re: Leland Ness book and the trench mortar battalions

#2

Post by hisashi » 10 Sep 2014, 02:45

Joan Pinyol wrote:On the other hand, the 20th. There are one 20th assigned to Ogasawara Fortress Corps, CO Captain Mitsuo Mizuashi, formed in April 1944 (or June). And there are another 20th assigned to the 57th Army in Japan (I don't know its CO). Perhaps this second 20th was formed after the first was disbanded in Iwo Jima in March 1945?
Ogasawara Fortress Corps(later 109th division) had 独立臼砲第20大隊 and 57th army had 迫撃砲第20大隊. The former had 12 pieces of 320 mm Type 98 mortar and 28 pieces of obsolete 75mm mortar. Though 迫撃砲連隊 in last-ditch divisions (201 202...) were planned to have Type 2 120mm Infantry Mortars, 迫撃砲第42大隊 in Okinawa had Type 97 81 mm infantry mortars. So I assume 迫撃砲第20大隊 also (was planned to) had 81mm mortars.
Joan Pinyol wrote: And finally, What happened with the 22nd, according with my notes in the 13th Army in China (CO: Tatsuji Motoda)? It not appears in Leland Ness book.
JACAR C12122440300 page 32
Raised in 25 Mar 1945 under 13th army. Moved to Shanghai in 12 Apr 1945, and was there until the end of war. The last CO, perhaps the only CO, was Capt.元田辰次 (Family name Genda or Motoda, given name Tatsuji).


Joan Pinyol
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Re: Leland Ness book and the trench mortar battalions

#3

Post by Joan Pinyol » 10 Sep 2014, 18:05

Thanks for your quick answer. The 2nd 20th (57th Army) was formed then after the 1st (Ogasawara Fortress) was disbanded?

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Re: Leland Ness book and the trench mortar battalions

#4

Post by hisashi » 10 Sep 2014, 18:39

We Japanese has difficulty in translating British Army Tank Brigades and Armored Brigades. In effect both are the brigades of tanks. I wrote 独立臼砲第20大隊 and 迫撃砲第20大隊 in Japanese to make clear the two formations are in different category. I don't know which of 1st army tank brigade and 1st armored brigade was raised earlier, but I am quite sure British men did not mind whether the other was using the same number.

According to JACAR C12121025100 迫撃砲第20大隊 was raised in 23 May 1945. It was after Kuribayashi sent his last telegram in Mar 1945, and before the last Japanese soldier in Iwojima surrendered in 1949.

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Re: Leland Ness book and the trench mortar battalions

#5

Post by Joan Pinyol » 10 Sep 2014, 20:39

Thanks a lot, Mr. Hisashi. Now it is clear enought.

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fontessa
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Re: Leland Ness book and the trench mortar battalions

#6

Post by fontessa » 10 Sep 2014, 21:46

Hello Pinyol,

There is the confusion about trench mortar battalions. IJA raised two kind of trench mortar battalions. The one was 迫撃第○○大隊 (Hakugeki Dai ○○ Daitai), and the other was 迫撃砲第○○大隊 (Hakugeki-hou Dai ○○ Daitai). The problem is that the English translation of both battalions is the same “trench mortar battalion”.

迫撃第23大隊~第40大隊 (Hakugeki Dai 23 Daitai ~ Dai 40 Daitai) were mobilized in accordance with Army Regulation “A” No. No. 34 dated 28 February, 1945,
迫撃砲第1大隊~第32大隊 (Hakugeki-hou Dai 1 Daitai ~ Dai 32 Daitai ) were mobilized in accordance with Army Regulation No.84 dated 23 May, 1945.
Both battalions were equipped with Type 2 12 cm trench mortars.

And there was another mortar (not trench mortar) battalion called 独立臼砲第○○大隊 (Dokuritsu Kyuhou Dai ○○ Daitai), ○○th independent mortar battalion. Ordinary these were equipped with Type98 32cm spigot mortars or 15cm mortars.
Joan Pinyol wrote: I concluded that the 23rd-32nd battalions of the first group and the 23rd-32nd battalions of the second group are the same.
The 2nd group was “Hakugeki-hou Daitai” and it differ from the 1st group “Hakugeki Daitai”.
Joan Pinyol wrote: Perhaps I am wrong, but I only found one trench battalion from 23rd to 32nd in Mutumi Encyclopaedia final position, in the demobilization reports, e.c.
The trench mortar battalions you found was 迫撃砲第23大隊~第32大隊 (Hakugeki-hou Dai 23 Daitai ~ Dai 32 Daitai ). On the other hand, 迫撃第23~32大隊 (Hakugeki Dai 23 Daitai ~ Dai 40 Daitai) were reorganized into 迫撃聯隊 (Hakugeki Rentai), trench mortar regimens, of the 200 series divisions. So it is natural you couldn’t find their final position, in the demobilization reports, etc.
Joan Pinyol wrote: The 2nd 20th (57th Army) was formed then after the 1st (Ogasawara Fortress) was disbanded?
“The 2nd 20th (57th Army)" was 迫撃砲第20大隊 (Hakugeki-hou Dai 20 Daitai). On the other hand, the 1st (Ogasawara Fortress) was 独立臼砲第20大隊 (Dokuritsu Kyuhou Dai 20 Daitai), and this was different unit from the 2nd 20th (57th Army).

fontessa

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Re: Leland Ness book and the trench mortar battalions

#7

Post by Joan Pinyol » 10 Sep 2014, 23:47

Much obliged Mr. Fontessa. Absolutly clear now. Only one question: When was issued the order to convert 迫撃第23~32大隊 (Hakugeki Dai 23 Daitai ~ Dai 40 Daitai) into 迫撃聯隊 (Hakugeki Rentai)?

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Re: Leland Ness book and the trench mortar battalions

#8

Post by Joan Pinyol » 11 Sep 2014, 08:43

Do you know to which army was assigned the 22nd Mortar Battalion (Hakugeki-hō Dai Daitai)? It is the only that not appears in the formerly quoted sources.

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Re: Leland Ness book and the trench mortar battalions

#9

Post by fontessa » 11 Sep 2014, 11:51

Hello Joan and hisashi,
Joan Pinyol wrote: When was issued the order to convert 迫撃第23~32大隊 (Hakugeki Dai 23 Daitai ~ Dai 40 Daitai) into 迫撃聯隊 (Hakugeki Rentai)?
The order was Army Regulation “A” No.61 dated on 2 April, 1945. If I say correctly, 迫撃第23大隊 ~ 第36大隊, 第38大隊 and 第39大隊 were converted to 迫撃聯隊 in accordance with this order, and it ordered the organization of the 200 series divisions, too. The below is the composition of the 200 series divisions
http://www.fontessa.info/hondokessenshi ... ibi_hengou
Joan Pinyol wrote: Do you know to which army was assigned the 22nd Mortar Battalion (Hakugeki-hō Dai Daitai)?
It was the 13th Area Army.
hisahi wrote: Though 迫撃砲連隊 in last-ditch divisions (201 202...) were planned to have Type 2 120mm Infantry Mortars, 迫撃砲第42大隊 in Okinawa had Type 97 81 mm infantry mortars. So I assume 迫撃砲第20大隊 also (was planned to) had 81mm mortars.
You have confused 迫撃大隊 with 迫撃砲大隊. One 迫撃聯隊 (Hakugeki Rentai) was reorganized from 2 迫撃大隊 (Hakugeki Daitai). Because one 迫撃大隊 (Hakugeki Daitai) had 18 Type 2 trench mortars, one 迫撃聯隊 had 36 Type 2 trench mortars. Thus 迫撃第32大隊~迫撃第40大隊 except 迫撃第37大隊 and 第40大隊 were reorganized into 迫撃聯隊. 迫撃第37大隊 and 第40 大隊 were subordinated to 55th Army and 52nd Army respectively. But the situation is different in the case of 迫撃第42・43大隊. They were reorganized from 独立迫撃第3~第10中隊 (Dokuritsu Hakugeki Chutai) in Okinawa. According to Senshi Sosho, the composition of a Dokuriti Hakugeki Chutai (independent trench mortar company) was as follow.
- Command Section
- 1st Mortar Platoon equipped with 6 Navy Type 3 8 cm trench mortars
- 2nd Mortar Platoon same as 1st Company
- Ammunition Platoon
The 3rd ~ 6th Independent Trench Mortar Companies were reorganized into 迫撃第42大隊, and the 7th ~ 10th Independent Trench Mortar Companies were reorganized into 迫撃第43大隊. So both 迫撃第42大隊 and 第43大隊 had 36 Navy Type 3 8 cm trench mortars each.

Navy Type 3 8 cm trench mortar was different from Army 九七式歩兵曲射砲 (Type 97 infantry mortar). But it could use Army Type 100 HE which Type 97 infantry mortar used.

fontessa

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Re: Leland Ness book and the trench mortar battalions

#10

Post by Joan Pinyol » 11 Sep 2014, 12:39

Excellent, Mr. Fontessa. I think that the "puzzle" is finished now.

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