Similar
- Male lead is a competent and ruggedly handsome general in his 30s-40s
- He is not a noble (if I recall correctly).
- He is falsely accused of being a rebel.
- Female lead is resourceful.
- Female lead forced to accept an arranged marriage.

Differences
- Male lead in The Rebel Princess treats the female lead with more respect, which I really appreciated.
- Obviously, the female lead in the The Rebel Princess is a princess. She's not a lowly illegitimate child like Moxi in Gone with the Rain.
- Higher production values and gorgeous costumes in The Rebel Princess.
- Longer drama, more focus on palace politics.