Writing style of Imperial Army signal messages


I'm doing some research into battles during the Pacific War and want to
include as much as I can from Japanese sourcs. The [Senshi
Sosho](https://en.wikipedia.org/wiki/Senshi_S%C5%8Dsho) contains valuable
accounts, but I keep coming across an odd style of writing when the writer
quotes text from original signal messages. It's obvious from first glance that
katakana is being used in place of hiragana, but there are also some strange
grammar and verb suffixes that I'm having trouble understanding.

I've attached an example segment I'm trying to understand at the moment.

[![enter image description
here](https://i.stack.imgur.com/7M3oQ.jpg)](https://i.stack.imgur.com/7M3oQ.jpg)

Here is the same text with the katakana replaced with hiragana:

西地区警備隊長は飽く迄「モシゲタ」周辺の地区を確保するに勉む **べし** 。面して敵軍「プリアカ」河口付近より有力部隊を前進 **せしめ**
「モシゲタ」の背後を衝くの **勢必至となるに至らば** 「プリアカ」河左岸に転進することを **得るも** 此の際 **と雖も** 他の警備地区内に一歩
**と雖も** 入ることを禁ず。

I think I get the first sentence, 'Commander Western Sector Guard Unit must
put all efforts into securing the zone around Mosigetta.' The only real
question I have is whether べし means べき?

The next sentence is full of confusion:

  * Who is doing the 面する (facing?)
  * せしめ means させ? What is め doing in there?
  * There seems to be a particle missing between 衝くの and 勢必至
  * How does 勢 affect 必至?
  * No idea what's going on with 勢必至となるに至らば except it probably talking about reaching モシゲタ.
  * 得るも = 得ても?

My fragmented attempt at translation: "Move your forces from the vicinity of
the mouth of the Puriaka where [where the enemy is], do you utmost to thrust
at the rear of Mosigetta; (勢必至となるに至らば) get them to shift to the left bank of
the Puriaka; [even at this time you are not permitted to take even one step
into other guard sectors"

I'm not looking for someone to translate it for me, but if I can get some
guidance on these confusing points I'll hopefully be able to put it together
myself. Thank you in advance.




Its style is called 普通文 and it developed from 漢文訓読体, which was used in literal
translations of Classical Chinese texts and was based on Old to Middle
Japanese grammar. 漢文訓読体 and 普通文 were widely used in official documents and
academic texts, as well as in texts translated from Chinese. You might want to
start with learning Classical Japanese (古文).

> Who is doing the 面する (facing?)

It’s not 面して, but 而して, which is a conjunction used almost only in 漢文訓読体.

Verb conjugation of Middle Japanese is different from that of Modern Japanese.
See <https://en.wikipedia.org/wiki/Early_Middle_Japanese#Conjugation>

> せしめ means させ? What is め doing in there?

It’s analyzed as せ (irrealis form of す “to do”, corresponding to ModJ する) + しめ
(infinitive form of しむ “to have sb. do”). 前進せしめ is equivalent to ModJ 前進させ.

> There seems to be a particle missing between 衝くの and 勢必至

Nothing is missing here. The の used in 漢文訓読体 rather sounds redundant to Modern
Japanese native speakers. It corresponds to a specific Classical Chinese 之,
which forms relative clauses.

> How does 勢 affect 必至?

勢 is the subject of 必至となる “to be unavoidable”.

> No idea what's going on with 勢必至となるに至らば except it probably talking about
> reaching モシゲタ.

「モシゲタ」の背後を衝くの勢必至となるに至らば means （敵軍有力部隊が）「モシゲタ」の背後を衝くこととなることが避けられない場合は

> 得るも = 得ても?

Partially yes. Here 得 is a verb, specific to 漢文訓読文, meaning “can”. Modern
Standard Japanese still uses 得る in this sense and it happens to be the only
surviving verb with upper-bigrade conjugation. E.g., ありうる “it is possible”,
ありえない “it is not possible”.

も here is a conjunction meaning “but, still, even if”. Therefore
“...に転進することを得るも” means “even though you can retreat to....” FYI, 転進 was
euphemism of 退却 used in WWII.

> 西地区警備隊長は飽く迄「モシゲタ」周辺の地区を確保するに勉むべし。
>
> Commander Western Sector Guard Unit must put all efforts into securing the
> zone around Mosigetta.

Your translation of the first sentence looks fine to me. In Modern Japanese,
it would be 西地区警備隊長は全力で「モシゲタ」周辺の地区を確保することに努めなければならない。

My translation of the second sentence

>
> 而して、敵軍「プリアカ」河口付近より有力部隊を前進せしめ「モシゲタ」の背後を衝くの勢必至となるに至らば「プリアカ」河左岸に転進することを得るも、此の際と雖も、他の警備地区内に一歩と雖も入ることを禁ず。

is
故に、敵軍が「プリアカ」河口付近から有力部隊を前進させ「モシゲタ」の背後を衝くこととなることが避けられない場合は「プリアカ」河左岸に退却してもよいが、この際であっても、他の警備地区内にただの一歩も入ることを禁じる。“Hence,
although when the enemy advance some strong troops from the mouth of the
Puriaka and they are surely to attack (our troops in?) Mosigetta in the rear,
you may retreat to the left bank of the Puriaka, even at this time you thus
are not permitted to take even one step into other guard sectors.”

