I'm researching Simo Häyhä for a school project and I'd like to use both Soviet and Finnish reports and documents about him or his actions during the Winter War. Thing is I'm having trouble finding these (probably because they're written in Russian and Finnish, neither of which shows up first on your regular internet search). I assume historians use this kind of sources rather frequently when researching similar topics and if anyone would like to share where they find them, I'd be grateful.
So, the Finnish Records will be located in the Finnish National Archives while the records of the Red Army up until 1940 are located in the Russian State Military Historical Archive (RGVIA) – the records from 1941 onward are located in the Central Archives of the Russian Defense Ministry. While the Finnish Archives offer an online order service for records, it is necessary for both archives to be able to read finding aids in the respective languages of Finnish and Russian. In the Russian case, it is also necessary to go to Moscow and review/copy the files in the archives. Lastly, it is necessary to emphasize that these files are also in their respective original languages and not available in English.
Basically, you need to speak both Finnish and Russian and go to Russia and Finland if you want to check these files out.
This is not only a tad ambitious for a school project but what you also need to know is that for the purpose of researching Häyhä, these files might not be useful at all whatsoever. You'd need to know the exact unit that either Häyhä was part of or – on the Soviet side – that was engaged by Häyhä on a specific date and even if you know that and you find them, in the Soviet documents, you might find nothing more than two or three sentences about how the unit was engaged by a sniper that day among the daily/weekly reports.
Frankly, I'd recommend to stick with books about Häyhä published in English rather than trying to find Finnish/Soviet military records as primary sources because that is a tad overambitious for a school project.
Hi - we as mods have approved this thread, because while this is a homework question, it is asking for clarification or resources, rather than the answer itself, which is fine according to our rules. This policy is further explained in this Rules Roundtable thread and this META Thread.
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An additional side note, but one which is pretty important to be clarified here, do you read Russian and/or Finnish? That will significantly affect any pointers you may receive. It seems so, but the way you phrased the issues with search seem to make that something to clarify.