Apologies, I've only read the first 20 or so chapters of GK a couple years ago and then I forgot what chapter I had left off on and so never got around to continuing it.
I was going to watch the anime but when I saw the dumb CGI bear I thought it'd be QUALITY and didn't end up watching it.
That said I do remember it at least started during the Russo-Japanese war, which would've been 1904-1905.
So you're mostly right, only it'd be,
Formosa > GK > Siberia > February 26th
The February 26th Incident took place in 1936, whereas the Siberian Intervention was 1918-1922.
If you want a great film about the Russo-Japanese war I'd recommend Battle of the Japan Sea ( https://www.imdb.com/title/tt0064733/
). I own it on DVD and am really glad I do.
It pretty accurately covers the entire war, including obscurer bits like how Japanese spies initially aided the bolsheviks in Russia to weaken the Russian government; ironic since they'd end up fighting these same bolsheviks in Siberia 13 years later.
In particular it did a really good job portraying General Nogi, who truly was a tragic figure.https://www.youtube.com/watch?v=siKTgOF9dfo