Masters of Mars3 books in series
Haydn of Mars Publisher's Summary
On Mars, in the distant future, the princess Haydn's arranged marriage cannot save her beloved Republic. Her arch-enemy, the warrior-woman Frane, seeks to make herself Queen while Haydn--the legitimate heir-- must flee for her life.
A reluctant symbol for those who would restore the monarchy, Haydn is too young and unprepared to assume the throne - but determined to become a great Queen. With a bounty on her head, she will make a perilous journey to the realization that - in order to save her world - she must sacrifice all that she holds dear.