WWII was a time when some sort of a military use was mandatory for most of the items produced at the time. Watches were no exception and Citizen was also involved in making military watches. One of them might be the one presented here. Seiko (and Seikosha) was the most prolific manufactures for military watches but this particular watch might be proof of the possible link between these two Japanese watch giants. 
The case is a in fact a transitional one, having a pocket watch body style inside an outer wrist watch case. It is chromed but both the casebacks are stainless steel. The case is small at 30mm diameter. Both of the parts have acrylic crystals. The outer case has lug holes. I think this could be an indicator that the watch had usual strap and not some type of nato as often seen on military watches (those have fixed lug bars). (read the comment below made by Keigo on nato straps) On the wristwatch part, the caseback reads: “Patent. no. 274740, Dust-Proof, Stainless steel, Back, 1428” Later edit thanks to Stephen: “Citizen’s research institute was called Shokosha.” The dial is simple with subsidiary seconds dial, at 6 o’clock. The arabic hour numerals are applied and so are the minutes markers on the outside. The overall design of the dial is carefully planned, with concentric parts and overlapping disks. The hands are blue, and they seem to be heated blue rather than painted. 
The movement is another mystery, to me at least. It looks like a Seiko calibre but is signed Citizen. So, is it Citizen or Seiko? In the end both of them got their inspiration from Swiss made movements. Later edit, thanks to Stephen: “The movement is the first version of the Citizen F-type. This was their first wristwatch, launched in 1931. It was based on a Swiss design and was used in several re-designed forms right through to the 1950s”. The strap is clearly a replacement. I don’t know how the original might have looked like, but I doubt the fact that it was a nato style. Yet again, it might have been. 
Here is one more piece of information I came across in my searches! Due to my friend Dobashi, now I have this awesome picture inside the firs Citizen factory where the worker coat has the same unusual logo seen in a circle on the movement. It is “CZ”, the Citizen logo. I have never seen this logo before and neither any of my Citizen collectors friends. Maybe this makes it one of the earlier watches EVER made by Citizen!? Year of production – 1931? (then, it’s not a military one) 
All things considered, I look at this watch and I can only imagine Japan before and during WWII and this watch doing it’s job, strapped on the wrist of it’s proud owner. Go to to the video of the movement here: https://vintagecitizenwatches.com/2014/04/14/the-first-citizen-wristwatch/ Read more about Citizen history here: https://vintagecitizenwatches.com/2013/12/26/citizen-history-from-1924/
Vintage Citizen Watches 
Hi Bogdan – the movement is the first version of the Citizen F-type. This was their first wristwatch, launched in 1931. It was based on a Swiss design and was used in several re-designed forms right through to the 1950s. The Seiko patent number is a mystery – maybe the case back was a replacement? Citizen’s research institute was called Shokosha.
Stephen aka Sweephand
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Stephen, thank you so much about your help! Your knowledge is very much appreciated! There is so much imformation about Citizen there to discover.
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Stephen, the case is not original to the watch. The “Stainless steel” term only appears in late 40’s, 50’s.
Best regards
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Thank you!
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Actually, most wrist waches of ww2 era had “traditional” leather straps, so called NATO strap was invented in early seventies for british military. http://gearpatrol.com/2014/01/07/icon-nato-strap/ Nylon – material of those type of straps also became available only after fifties, before that they used canvas for military watches, mostly for U.S. army.
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Thank you for your comment. So… in fact it was an open-end strap?
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“The Fusion of Technology and Beauty” Citizen has never betrayed this motto, love their watches both in the design and function aspects.
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Thanks for your comment! It is indeed a wonderful world – Citizen world. 🙂
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Hi, don`t forget, the Japanese were fighting in China in 1931 so it very well could be a military watch.
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Thank you! That is an interesting point of view!
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Should have added, I own quite a few Citizen watches I picked up while living in Japan, some appear to be quite old, I`d like to send you pics if you give me an address I can send them to
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That would be great! Thank you! I will write you on the email address provided.
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HI, I have this watch fitted with a Rolex Marconi movement that appears to be originally fitted it it. There is no corrosion on the case, it looks new. I am curious, if the watch was made by Seiko why is it written in English? There is nothing on mine to indicate it was produced in Japan. Was this perhaps a case produced in England and sold to various companies around the world?
Thank you, Seznthn
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Hello! I doubt the fact that you have this watch. First of all you talk about Rolex, then Seiko and this watch is Citizen. Sorry but I don’t see the connection.
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At the top of the page the discussion mentioned a Seiko watch. I should have written Citizen, instead of Seiko. I apologize for the confusion. However there is no reason to doubt I have the watch though. I have seen the exact same watch signed Seiko as well. In addition I have seen another example signed Rolex Marconi with an enamel dial. My question is still the same. Why do you think these cases were written in English? Could the cases have been produced in England originally and those patent numbers are British Patents? I suspect so, that is why some were fitted with Marconi movements.
Regards, S
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I see. Can you please upload some pics? I have seen Rolex movement in pocket watch Citizen, never as a wristwatch.
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I will send you a link to my watch, which I am offering for sale on 1stdibs.com. It will post tomorrow a link to it. Can I post a link here or is there another way you would like me to do it?
S
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Post the link. 😉
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I just picked
up a ww2 citizen with the same logo on movement and a 24 hr dial. love to send pics to find out more about it Thanks William
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Cool! Can you post the pics here? This way others may see them and maybe more info will be provided.
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How do you upload pics?
Thanks
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Hello I have a citizen watch that was taken from a Japanese Officer in WW2 with the capture papers and his cigarette case. How do I find out if its rare?
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Hi! Send me an email with some pics at citizen.guy@mail.com or post them here. Will take a look.
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Sorry but I dont know how to post pics.
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Email them and I will look.
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