If you have a character whose background you want to explain in a natural way, you can do so through anecdotes, not direct Wikipedia-like explanations.

No real (or sane) person is going to approach you all of the sudden and say “I was in the military in the 1600s, at age of 16, my father was a captan and blah blah blah blah…”

But there will be people who will say in a casual way “In the army they gave us nice caps, but I stopped wearing them for fear of going bald at a young age”.

With that you explain the background and also the character’s character in a short, simple and yet interesting way.

EDIT: The stupid draft I had saved had not been updated as it should and the incomplete version of what I wanted to say was published. I have corrected it.