There's really 2 that apply here, so I'll do both
1. Who and what?
Nakajima Nobutada, a young, idealistic direct retainer to the shogun.
2. Where and when?
Japan, ca. Feb. 1844-July 12, 1868.
3. Why was this your favorite?
Because I met/fought alongside many of the people I'm studying as a professional historian (in training) now. Also because I spent it with my soulmate, whom I married despite the objections of my family.
4. The most important lesson in that life?
That loyalty is paramount, and that when a cause is truly worth dying for, then by all means...
5. Anything you like to mention...
I don't want to get gunned down in a battle ever again...
AND
1. Who and what?
Kimura Sadao (or Kazuo, not really sure), Imperial Japanese Navy fighter pilot.
2. Where and when?
Started out in Sendai (northern Japan), spent my career in the Navy up to my death in 1945 in Tokyo.
3. Why was this your favorite?
Because of the fact that it was essentially nothing but warm fuzzy romantic memories (despite all the horrible stuff going on in Japan and in the world) up till 1942. Once again, I married my soulmate, but this time it was an arranged marriage. I love how even after the war got really bad, she had this childlike innocence about her and had a smile that always warmed my heart.
4. The most important lesson in that life?
I committed ritual suicide at the end of the war-- and I know now that to break the cycle I seem trapped in of always dying in war, I must live, at least for the sake of my soulmate, instead of dying for her.
5. Anything you like to mention...
The squid on a stick in one of the stalls in Asakusa Temple was AMAZING back then...
--N.