IJA divisions: an overview

[hisashi]

Peter, thank you for your comment. This kind of 'Record says' posting seldom have any comments.

By the end of war, those divisions moved from Manchuria and China. Here is the final location chart.

From Manchuria: 14 divs (all divisions!)

1 Philippine
8 Philippine
9 Taiwan
10 Philippine
11 Japan
12 Taiwan
14 Palau
23 Philippine
24 Okinawa
25 Japan
28 Miyakojima Island (nearby Okinawa)
29 Guam/Saipan/Tenian
57 Japan
71 Taiwan

From China/Mongolia: 8 divs (plus 2 divs to Manchuria)

15 Burma
17 Rabaul/Bougenvalle
22 Burma/Thailand
26 Philippine
32 Halmahera(Indonesia)
http://en.wikipedia.org/wiki/Halmahera
35 West New Guinea
36 Biak
37 Thailand/Malaysia
(39 to Manchuria)
(59 to Manchuria)

Defensive divisions and IMBs fulfilled the gap of them. To the end of war, more and more inferior divisions were raised mainly in Japan.

[Peter H]

One thing I can't reconcile is differing Allied views of Japanese Divisional capabilities.

This link ( http://www-cgsc.army.mil/carl/resources ... /Huber.asp ) states at Okinawa in 1945:

"[Japanese]staff calculated that superior quality and numbers of weapons gave each U.S. division five or six times the firepower of a Japanese division".

I assume American intelligence came to the same conclusion.

Fair enough but in 1942,1943 as in the case of Arakan,Burma single Japanese divisions were treated by the Allies as feared entities,veteran formations that needed at least a Corps to counter them.Firepower alone did not play much in this analysis,the elan and swift outflanking attacks of the Japanese infantry being primarily commented on as a factor.

[hisashi]

IJA had inferior artillery and tank formation in comparison with its infantry strength, but in the offensive IJA air force was strong enough for ground support. I think the success of IJA in the beginning of the Pacific War owed to the inferior status of allied air force in Asia. At least IJAAF prevented IJA ground force from heavy loss by relatively strong allied artilleries.

[hisashi]

<To-the-root mobilization>

In 1945 Japan mobilized more and more divisions and IMBs in Japan and Manchuria. nekosogi doin (to-the-root mobilization) was a phrase for this extreme gathering of adult male regardless of readiness for military service.

<pinned-up division and mobile division>

Perhaps inofficially, IJA called some of formations raised in this period as pinned-up (haritsuke) formations. It meant they were for initial waterfront defense. Mobile (kido) formations were better equipped ones for reaction.

<IMBs raised in 1945>

IJA raised the following 54 IMBs in 1945. Many of them were still in build at teh end of war.

Reorganization of fortress troop:
75 76 100 118 122

In Manchuria, from small troops or newly from local Japanese residents:
77 78 79 80 130 131 132 133 134 135 136

In China, reorganizing army level field replacement troop:
81 82 83 84 85 90 91 92

In China, from personnels left by divisions moved from China:
86 87 88 89

Old-fashioned artillery (e.g.240mm heavy cannon) with infantries as pinned-up formations:
95 96 97 98

Reorganization of small garrisons and/or troops interrupted of move in a port in Japan and Taiwan:
101 102 103 112 126 129

Reorganization of overseas garrisons :
105 128

Newly raised for local defense:
108 109 113 114 115 116 117 119 120 121 123 124 127

Reorganization of 3rd sea mobile brigade (reinforced with landing boats):
125

<divisions raised in 1945>

IJA raised 66 divisions in 1945.

In Manchuria, from small troops or newly from local Japanese residents:
121 122 123(from 57th IMB) 124 125 126 127 128
134(from 78th IMB) 135(from 77th IMB) 136 137 138 139 148 149 158

In China, from small troops:
129 130 (both from 19th IMB) 131 132 133 161

Pinned-up divisions for the defense of Japan:
140 142 143 144 145 146 147 151 152 153 154 155 156 157
303 308 312 316 321 322 344 351 354 355

Pinned-up divisions for the defense of Korea:
150 160 320

Mobile divisions for the defense of Japan:
201 202 205 206 209 212 214 216 221 222 224 225 229 230 231 234

Many of them were not only understrength, but also lacked basic weapons such as rifles.

158th division was the only IJA field division which did not have any divisional commander. Ordered to raise 158th in Aug 10, before divisional commander was officially assigned Soviet invaded to Manchuria.

-end of article-

[Eugen Pinak]

Hisashi - thank you very much! You wrote a great reference article - short, yet detailed.

[Peter H]

Regarding the Mobile divisions in Japan in 1945.

Coox(Kogun) has this to say:

On April 2, IGHQ activated eight crack divisions, comprising the strength for decisive battle.These troops prided themselves upon their "youthfulness;" their young and high-spirited staff officers, from division commanders down; and their high proportion of active-duty soldiers...The eight elite divisions were the 201st, 202d, 205th, 206th, 209th, 212th, 214th, and 216th.

Thus it was still possible to raise "elite" formations in the defence of the homeland.I assume these divisions were well equipped as well.

[hisashi]

In Mainland Japan, the mobilization in 1945 had three waves. April was the second wave, and the rest of 2xx series mobile division was in third wave.
201-216 divisions had three IRs, an artillery (75mm gun) regiment, a mortar regiment, high-velocity (AT) gun unit and AA machinegun unit. All those unit in the eight divisions had secret code (similar to feldpost number in wehrmacht) so some element of each troop perhaps existed even if understrengthed. Other mobile divisions usually lacked the artillery regiment. Pinned-up divisions had only one support gun unit; AT gun, mortar or rocket unit.

It seemed that mobile divisions received as many new young draftees instead of untrained old men. Surely IJA did their best to give mobile divisions relatively better resources but training was limited and equipments were in short. Perhaps the most trusted formations were divisions called back to Japan; 11 25 and 57 divs. Divisions raised by 1944 and stayed in Japan, 1st IGD 3rd IGD 7 42 44 72 73 77 81 84 86 and 93 divs perhaps had much better weapons and trained personnels though they might be averagely old.

[hisashi]

I noticed I missed two divisions raised in 1943.

Even after 1941, some divisions had four infantry regiments because they were raised with reserve personnels and considered inferior in individual soldiers' quality. 30th and 31st division were the last divisions which received the last regiemnts from square divisions. Here is the list of divisions which gave up a regiment.

30th <-5th, 19th, 20th (May 1943)
31st <-13th, 18th, 116th (Mar 1943)

The date is the creation of new division but the join of regiments varied respectively.

[stulev]

The 41st Infantry Regiment was seeded to the 30th Division by the 5th division - The 41st was rendered ineffective while fighting with the Horii detachment in New Guinea. several questions

would members of the old 41st be part of the reformed regiment/ Send from New Guinea to the Philippines to be core of new regiment.

Unit code - I only have a unit code for the 41st when it was attached to the 30th -- 12023 -- it should have also had a code with the 5th division maybe 5175 which is unused on my listing for the division

the 74th Infantry Regiment carries the 30th divisions 12024 but I also have a 19th Division number also 8503 and the 77th has 12025 and also 2052 of the 20th Division.

The 20th division was in New Guinea in Jan 1943 and re-organized in June 1943 - - would they detach and send back to Philippines when the rest of the Division was engaged with the Australians and Americans

[Peter H]

..would members of the old 41st be part of the reformed regiment/ Send from New Guinea to the Philippines to be core of new regiment.

The Nankai Shitai 144th Regiment survivors at Rabaul in 1943 ( 236 men) were transferred to Burma to rejoin their parent 55th Division so it appears where possible such a policy was followed.

[stulev]

I suppose that is true - divisions tended to be formed from localized sources - even replacements came from their local Depot Division - --- I am not sure when a division received regiments from 3 different divisions that they could keep the local flavor intact.

[hisashi]

Several times from 1868 to 1945 each regiment revised the border of regimental district. One day soldiers found novices from other regions, sometimes totally different part of Japan. They went along with it.

109th division at Iwojima was one of the worst patchwork of small troops from old reserve personnel.

http://forum.axishistory.com/viewtopic.php?f=65&t=91386

[Kelvin]

HI, I would like to ask about motor type divisions in Japanese Army. In accordance with TOE, Japanese motor division had 656 trucks and 69 cars in 1941.

I would want to know if any motorcycles possessed by those division too ? I know they had bicycle in 1941, how many those three divisions bicycles they possessed (5, 48 and Guards divisions) in authorized TOE ?

And Each motor infantry regiment had 87 trucks and 5th division had four infantry regiments, so even the fourth regiment were motorized too ? Thank

[Akira Takizawa]

> I would want to know if any motorcycles possessed by those division too ?

I don't know.

> I know they had bicycle in 1941, how many those three divisions bicycles they possessed (5, 48 and Guards divisions) in authorized TOE ?

They were unauthorized equipments.

> And Each motor infantry regiment had 87 trucks and 5th division had four infantry regiments, so even the fourth regiment were motorized too ?

All were motorized.

Taki

[Kelvin]

Hello, Taki, thank for that. I don't understand it why motor type division 's medical units were equipped with 88 horses instead of motor, but all units were motorized already.

I would like to ask 18th division, if this division was authorized to have any motor vehicles in late 1941, I see her 1937 TOE, she only had 5,493 horses. Any truck or car for her in 1941 ?