I enjoyed this Japanese-language film on normal life in the the occupied city of Shenyang:
But this was a real gem: a History-Channel-style 10 part series on “The Battle of Manchuria” (part 1 of 10 here). It really gets going around the 2′ mark, and then at 3’37” we get rolling with the Russo-Japanese War. Matsuoka shows up at the League of Nations at 8’40”: