Strzelcy. Inwazja na Hiszpanię, 1809

The realism added so much depth to the story, but I wonder whether Bernard Cornwell drew on personal experience or extensive research for these scenes.

The choices made under pressure really made me think about what I would do in similar situations. Did the characters' struggles resonate with others as much as they did with me?

I'm curious whether Cornwell took creative liberties or stayed strictly true to the timeline. For history buffs, how accurate is this depiction overall?